[1.9] Lift code freeze

[enisoc]

I propose that we lift code freeze on Wed, Dec 13. We expect all the current PRs in the milestone to merge before then.

This will involve undoing the submit queue config from #32.

However, we will maintain the milestone bot config in freeze mode until the 1.9.0 release goes out.

cc @marun @jberkus @spiffxp