Switch to tagged devcontainer

[opajonk]

WIth this change, a semver-tagged devcontainer version is pinned. Thus, updates to the "latest" tag cannot unexpectedly cause harm to the repository anymore.

[github-actions]

⚠️ Docs-as-Code version mismatch detected
Please check the CI build logs for details and align the documentation version with the Bazel dependency.

[opajonk]

I checked the following to test the container:

bazel test //...
bazel run //:docs
bazel run //:ide_support

Those passed fine.

In the README, a target bazel coverage --combined_report=lcov //docs:score_metamodel_test is mentioned. However, this target does not exist (anymore?). The target bazel run //:format.check does not work since it expands to three targets. Running those individually worked.

[github-actions]

The created documentation from the pull request is available at: docu-html