allowing backports into non-LTS releases

[Dan Streetman]

I'd like to propose changing our rules to allow - but not require -
backports into non-LTS releases. I think it makes sense to allow this,
so the benefit of backports can be provided in non-LTS releases as
well.

As we currently do have backports in the non-LTS lunar and mantic
queues, and we've rescheduled our next meeting until the end of next
month, if you have time @teward and @mapreri I'd like to discuss over
the ML, so we can accept (or reject) the non-LTS uploads.

Thanks!