Support a GitHub comment trigger for re-running the CLA process

[jeffhandley]

Any time the CLA bot fails to run on a PR (for various reasons), contributors and maintainers have to remember the best way to force the bot to rerun itself. A @microsoft-github-policy-service rerun command or something similar would be very useful. Simply tagging @microsoft-github-policy-service or issuing @microsoft-github-policy-service help could even yield a comment that talks about when rerun is needed and how to use it.

Closing and reopening the PR is our go-to stop-gap, but that is an annoying step to have to take, especially when there are PR checks that take hours to run and we want to avoid stopping or rerunning them.

[DragosDanielBoia]

thanks for the feedback @jeffhandley , today github had a lot of issue, yes is going to be useful to implement this command "@microsoft-github-policy-service rerun" and we are going to do it.

[dougbu]

We in .NET Core-Eng field frequent requests about failed CLA checks and don't have good recommendations other than to close and reopen the affected PRs. Doing this would make our lives easier❕

[jeffwilcox]

Any input from people on rerun vs reprocess on the command?

[DragosDanielBoia]

@jeffhandley the rerun command is now in prod, this is the command for dotnet org: Will close the issue.

@dotnet-policy-service rerun