Missing installation ID after repo rename

[premun]

We have another case of repo renaming and BAR missing its installation ID.
When this happens, users are unable to create subscriptions because the DB is missing the installation ID row for the renamed repository.

We can actually go and query the ID easily so we can do that for the user when they try to create the first subscription for the new repo:
https://docs.github.com/en/rest/apps/apps?apiVersion=2022-11-28#get-a-repository-installation-for-the-authenticated-app

We need the installation ID to get a token against the repository through the GitHub app.

[premun]

@dkurepa please roll this out and try creating a subscription targeting https://github.com/dotnet/yarp (they asked for Arcade subscription specifically).

[dkurepa]

The feature implemented in #4427 worked. I was able to create a subscription dotnet/yarp, without manually adding the subscription ID in BAR