Update Alpine base image to latest 3.x version

[ThorbenLindhauer]

Acceptance Criteria (Required on creation)

• The version of Alpine Linux that we use as the base image for our Docker images is updated to the latest minor release

Hints

• Check Alpine update guide for any incompatibilities that may affect us or our users
• Consider if this needs backporting

Links

Breakdown

### docker-camunda-bpm-platform Pull requests
- [ ] https://github.com/camunda/docker-camunda-bpm-platform/pull/270
- [ ] https://github.com/camunda/docker-camunda-bpm-platform/pull/271
- [ ] https://github.com/camunda/docker-camunda-bpm-platform/pull/272
- [ ] https://github.com/camunda/docker-camunda-bpm-platform/pull/273

### camunda-docs-manual Pull requests
- [ ] https://github.com/camunda/camunda-docs-manual/pull/1491
- [ ] https://github.com/camunda/camunda-docs-manual/pull/1492
- [ ] https://github.com/camunda/camunda-docs-manual/pull/1493
- [ ] https://github.com/camunda/camunda-docs-manual/pull/1494

Update - Version & Release Note Amendments

### camunda-docs-manual Pull requests
- [ ] https://github.com/camunda/camunda-docs-manual/pull/1499
- [ ] https://github.com/camunda/camunda-docs-manual/pull/1500
- [ ] https://github.com/camunda/camunda-docs-manual/pull/1501
- [ ] https://github.com/camunda/camunda-docs-manual/pull/1502

Dev2QA handover

• [ ] Does this ticket need a QA test and the testing goals are not clear from the description? Add a Dev2QA handover comment

[psavidis]

Release Notes:

• 3.16.0 Release Notes, Blogpost
• 3.17.0 Release Notes, Blogpost
• 3.18.0 Release Notes, Blogpost

[psavidis]

• There is a notable mention in the release notes about a docker package shipped with the latest alpine image has some changes. Not sure if this means something for our docker offering. The builld of docker-camunda-bpm-platform docker image using earlier docker version 20.10.8 appears functional.

[mboskamp]

The existing PRs all look good. 👍 I guess we also want to backport it to 7.17 as well. Can you add another PR? Before closing this issue, please don't forget to add the version labels.

[psavidis]

I've added a backport PR for 7.17 as well.

[psavidis]

Update:

eol of 7.17 (October 2023) is before eol of alpine 3.15 (24 Nov 2021, source here) which renders the backport for 7.17 unnecessary. Thus, i recommend not to include it in our consideration.

[mboskamp]

As discussed, let's do the backport to 7.17 too. The benefits are that 7.17 will go EOL with an updated version and we might avoid security issues until then or even after the official support, which would be nice for our users.

[tasso94]

@psavidis, even though there are no obvious breaking changes, let's mention in the migration ^1 and patch-level update ^2 guides that from what to what versions we updated the alpine base image and link the release notes. Like this, our users will be made aware that they must double-check their customizations.

[psavidis]

Docs for minor/patch - level upgrade have been added.

[mboskamp]

@psavidis, this looks very good already 👍 The docker branches are ready to be merged. I left two hints in the docs master PR which would need to be backported to the other branches as well if you agree with my opinion. Let me know what you think in the PR :)

[psavidis]

@psavidis, this looks very good already 👍 The docker branches are ready to be merged. I left two hints in the docs master PR which would need to be backported to the other branches as well if you agree with my opinion. Let me know what you think in the PR :)

I've applied your suggestions as indicated both to master & backports 👍

[mboskamp]

Awesome, everything looks great. Well done :)

[tasso94]

@psavidis, can you please add to the migration guides/update guides that our docker images have been updated from version 3.15 and add the release notes of 3.16 and 3.17 as well?