Generated baseline update PRs for internal branches

[mthalman]

Currently the pipelines like the SDK diff and license scan pipelines will not automatically create PRs to update baseline files when running on an internal branch. The logic currently only uses the GitHub CLI to create PRs and we wouldn't want to do push that to GitHub for content coming from an internal branch to avoid unintended information disclosure. Instead, we should consider creating a PR in the AzDO repo. This would provide convenience for the SB monitor role.

[MichaelSimons]

The use of DarcLib may be useful here as it has abstractions for working against either GH or AzDO.

[ellahathaway]

Echoing the importance of this per the situation described in https://github.com/dotnet/release/issues/1579#issuecomment-3378888732