Add vscode devcontainer / github codespaces

[sduquemesa]

Context: Have you dream of having many and completely environments (down to the operative system) on your local machine or even making changes to the walrus online?

Description of the Change: This PR implements a fully furnished vscode devcontainer.

Benefits:

• Can create fully reproducible environments on different machines
• Enables (paid) github codespaces
• Allows you to run/debug the walrus on linux even when on a mac or windows machine

How-to?

• To try it out the devcontainer locally on vscode follow the instructions here,
• Use (paid, yes you pay so be careful with usage) github codespaces

Possible Drawbacks: 🤷

Related GitHub Issues: None

[sduquemesa]

I have added this PR mainly for convenience: this is how I run and debug the walrus on linux while using a mac machine. This PR does not have yet a reviewer — if you think this is useful and can review it, go for it!

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Comparison is base (544c457) 100.00% compared to head (436403a) 100.00%. Report is 1 commits behind head on master.

:exclamation: Current head 436403a differs from pull request most recent head 665e9df. Consider uploading reports for the commit 665e9df to get more accurate results

Additional details and impacted files

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