Add dev container config

[crazy4pi314]

Adding config for scikit-image for the open spec, Development Containers, which allows tools like VS Code, Codespaces, JetBrains tools, DevPod, and hopefully more soon (GitPod?)

initially drafted this at SciPy 2023 sprints with @lagru <3

Checklist

✅ A descriptive but concise pull request title
✅ Docstrings for all functions
✅ Unit tests
✅ A gallery example in ./doc/examples for new features
✅ Contribution guide is followed

Release note

Summarize the introduced changes in the code block below in one or a few sentences. The
summary will be included in the next release notes automatically:

Added configuration files for tools that support the [Dev Container spec](https://containers.dev/). Makes it easier for contributors and maintainers to ensure reproducable workspaces.

[lagru]

Thanks! Looks good as a first glance. Is there some way to test this configuration out already or do we need to merge this first?

[crazy4pi314]

I think you can try it out on the PR page here if you go to the top right and click the code dropdown button:

[lagru]

Ah, seems to work. There's actually a complete environment under ~/envs/skimage-dev. Though, it's not activated by default inside the terminal. Can we achieve that somehow?

[lagru]

I was surprised that pre-commit worked before the development setup in postBuild. Seems like it is included in the container by default

$ which pre-commit
/usr/local/py-utils/bin/pre-commit

[lagru]

Suggested change

	spin docs
	spin docs
	source ~/envs/skimage-dev/bin/activate
	pre-commit install

[lagru]

Suggested change

	"postCreateCommand": "pre-commit install && bash ./.devcontainer/postBuild",
	"postCreateCommand": "bash ./.devcontainer/postBuild",

Just to be safe it may be good to use the pre-commit in from the dev environment.

[github-actions]

Hello scikit-image core devs! There hasn't been any activity on this PR for more than 180 days. I have marked it as "dormant" to make it easy to find.
To our contributors, thank you for your contribution and apologies if this contribution fell through the cracks! Hopefully this ping will help bring some fresh attention to the review. If you need help, you can always reach out on our forum
If you think that this PR is no longer relevant, you may close it, or we may do it at some point (either way, it will be done manually). If you think the PR is valuable but you no longer have the bandwidth to update it, please let us know, so that someone can take it over. 🙏