We are unable to update the github plugin beyond v1.29.2 (don't judge) due to a logic change in getCommitSHA1 which breaks status reporting for us.
Prior to v1.29.3, when multiple build sources are present, the SHA1 of the first source was returned.
Starting with v1.29.3, the source repo name needs to contain the project name or else no SHA1 will be returned.

I have a fix (I'll happily put up a PR if that's appropriate) which falls back to the old logic (return the SHA1 of the first build source) when the project name doesn't match any of the repos.