Enable the installation of extensions after starting code-server

[atheo89]

Related to: https://issues.redhat.com/browse/RHOAIENG-6392

Description

This PR allow the extensions get installed after code-server start.

How Has This Been Tested?

Playground Cluster: https://rhods-dashboard-redhat-ods-applications.apps.dis-210nightly.osp.rh-ods.com/notebookController/spawner

1. Build and push the image on the mirror registry for the disconnected
2. Built image: bastion.dis-210nightly.osp.rh-ods.com:8443/modh/codeserver:v1 or alternatively bastion.dis-210nightly.osp.rh-ods.com:8443/modh/codeserver@sha256:b8b999bbcf86dcfcf1029ebb9f5fa77b58c9ef2fb75123a7b4d6643a2746f061
3. Spin up an disconnected cluster
4. Edit code-server-notebook ImageStream by adding a new tag with the above image.

   - name: background-installation
     annotations:
       opendatahub.io/notebook-build-commit: db8bd76
       opendatahub.io/notebook-python-dependencies: '[{"name":"code-server","version":"4.22"}]'
       opendatahub.io/notebook-software: '[{"name":"Python","version":"v3.9"}]'
       opendatahub.io/workbench-image-recommended: 'false'
       openshift.io/imported-from: quay.io/modh/codeserver
     from:
       kind: DockerImage
       name: 'bastion.dis-210nightly.osp.rh-ods.com:8443/modh/codeserver@sha256:b8b999bbcf86dcfcf1029ebb9f5fa77b58c9ef2fb75123a7b4d6643a2746f061'
     generation: 8
     importPolicy:
       importMode: Legacy
     referencePolicy:
       type: Source

5. Spin up a new notebook, using background-installation tag
6. Check if the status is Running
7. Navigate to newly created notebook and check the logs. (It takes a bit of time to initialize the installation)
8. The logs should looks like the following:

   spawn-fcgi: child spawned successfully: PID: 10
   Debug: User directory not found, creating '/opt/app-root/src/.local/share/code-server/User/'...
   Debug: '/opt/app-root/src/.local/share/code-server/User/settings.json' file created.
   Running command: /usr/bin/code-server --bind-addr 0.0.0.0:8787 --disable-telemetry --auth none --disable-update-check /opt/app-root/src
   [2024-05-13T12:10:14.719Z] info Wrote default config file to /opt/app-root/src/.config/code-server/config.yaml
   code-server is ready.
   [2024-05-13T12:10:15.151Z] info code-server 4.22.0 e5d145fdf32e82be2a0f8de9a3b05f65b13052b6
   [2024-05-13T12:10:15.152Z] info Using user-data-dir /opt/app-root/src/.local/share/code-server
   [2024-05-13T12:10:15.173Z] info Using config file /opt/app-root/src/.config/code-server/config.yaml
   [2024-05-13T12:10:15.173Z] info HTTP server listening on http://0.0.0.0:8787/
   [2024-05-13T12:10:15.173Z] info - Authentication is disabled
   [2024-05-13T12:10:15.173Z] info - Not serving HTTPS
   [2024-05-13T12:10:15.173Z] info Session server listening on /opt/app-root/src/.local/share/code-server/code-server-ipc.sock
   127.0.0.1 - htpasswd-cluster-admin-user [13/May/2024:12:10:53 +0000] "GET /notebook/test/cs1 HTTP/1.1" 302 145 "https://oauth-openshift.apps.dis-210nightly.osp.rh-ods.com/" "Mozilla/5.0 (X11; Linux x86_64; rv:125.0) Gecko/20100101 Firefox/125.0" "10.0.179.217, 10.131.0.2"
   [12:10:53]
   [12:10:53] Extension host agent started.
   File not found: /usr/lib/code-server/lib/vscode/out/vsda.js
   File not found: /usr/lib/code-server/lib/vscode/out/vsda_bg.wasm
   [12:10:56] [127.0.0.1][789a0ff1][ManagementConnection] New connection established.
   [12:10:58] [127.0.0.1][fcc613af][ExtensionHostConnection] New connection established.
   [12:10:58] [127.0.0.1][fcc613af][ExtensionHostConnection] <129> Launched Extension Host Process.
   No internet connection. Installing all extensions.
   Installing extensions...
   Extension 'ms-python.python-2024.2.1.vsix' was successfully installed.
   [12:17:45] Extensions added from another source ms-python.python file:///opt/app-root/src/.local/share/code-server/extensions/extensions.json
   Installing extensions...
   Extension 'ms-python.debugpy-2024.2.0@linux-x64.vsix' was successfully installed.
   [12:17:51] Extensions added from another source ms-python.debugpy file:///opt/app-root/src/.local/share/code-server/extensions/extensions.json
   Installing extensions...
   Extension 'ms-toolsai.jupyter-2023.9.100.vsix' was successfully installed.
   [12:20:04] Extensions added from another source ms-toolsai.jupyter file:///opt/app-root/src/.local/share/code-server/extensions/extensions.json
   Installing extensions...
   Extension 'ms-toolsai.jupyter-keymap-1.1.2.vsix' was successfully installed.
   [12:20:05] Extensions added from another source ms-toolsai.jupyter-keymap file:///opt/app-root/src/.local/share/code-server/extensions/extensions.json
   Installing extensions...
   Extension 'ms-toolsai.jupyter-renderers-1.0.17.vsix' was successfully installed.
   [12:20:07] Extensions added from another source ms-toolsai.jupyter-renderers file:///opt/app-root/src/.local/share/code-server/extensions/extensions.json
   Installing extensions...
   Extension 'ms-toolsai.vscode-jupyter-cell-tags-0.1.8.vsix' was successfully installed.
   [12:20:08] Extensions added from another source ms-toolsai.vscode-jupyter-cell-tags file:///opt/app-root/src/.local/share/code-server/extensions/extensions.json
   Installing extensions...
   Extension 'ms-toolsai.vscode-jupyter-slideshow-0.1.5.vsix' was successfully installed.
   [12:20:09] Extensions added from another source ms-toolsai.vscode-jupyter-slideshow file:///opt/app-root/src/.local/share/code-server/extensions/extensions.json

Merge criteria:

• [x] The commits are squashed in a cohesive manner and have meaningful messages.
• [x] Testing instructions have been added in the PR body (for PRs involving changes that are not immediately obvious).
• [x] The developer has manually tested the changes and verified that the changes work

[openshift-ci[bot]]

[APPROVALNOTIFIER] This PR is NOT APPROVED

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[openshift-ci[bot]]

@atheo89: The following tests failed, say /retest to rerun all failed tests or /retest-required to rerun all mandatory failed tests:

Test name	Commit	Details	Required	Rerun command
ci/prow/images	ba9d85becafd4a2a5c0c3f341fa58b5fc371f6df	link	true	/test images
ci/prow/notebooks-e2e-tests	ba9d85becafd4a2a5c0c3f341fa58b5fc371f6df	link	true	/test notebooks-e2e-tests

Full PR test history. Your PR dashboard.

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[atheo89]

Close this in favor of https://github.com/opendatahub-io/notebooks/pull/532