Need a way to associate releases to metadata versions

Today, we take a snapshot from https://graph.microsoft.com/beta/$metadata, write it to https://github.com/microsoftgraph/msgraph-metadata/blob/master/beta_metadata.xml and then continue with XSLT and SDK generation. After the generation, there is no easy way to associate SDK release to which version of metadata it has consumed.

One can go to release date, check when the PR is opened, then associate the date/time of that to the beta_metadata.xml version, but this is a long path. And it can cause confusion when the releases are skipped or PRs take long time etc.

I would propose one or more of the following:

1. Having a link to beta_metadata.xml file in release notes with a commit hash. Linking to main branch won't work as the branch moves forward.
2. Checking in the version of beta_metadata.xml into msgraph-beta-sdk-dotnet repo. Release notes already link to a snapshot of the repository at the time of release.
3. Having a folder for releases in msgraph-metadata to keep the snapshots of metadata.

The argument for option 3 vs option 2 is that metadata files will live metadata repo, where SDK goes to SDK repo. But doing this in metadata repo can't be language-agnostic, given that SDK generations for different languages are independently versioned.

Same issue should be addressed for v1.0 as well.
AB#7134

Start by reviewing the release process around beta_metadata.xml in the msgraph-metadata repository and the release notes in msgraph-beta-sdk-dotnet. Compare the proposed commit-hash link, checked-in metadata version, and metadata release-folder approaches, including how the same decision would apply to v1.0; done means selecting and documenting an unambiguous association between each SDK release and its metadata snapshot.