Delete inactive branches on the upstream repository

[ljmf00]

We should avoid publishing branches to the upstream repository and leave them stale, indefinitely. About the ones listed below -- is any of these required other than stable?

[ibuclaw]

I'd rather not delete other people's work.

[ljmf00]

I'd rather not delete other people's work.

Sure, but that should be in their tree's, not on the upstream.

[ljmf00]

Also, dcache is synced with master, so no extra diffs there. @RazvanN7 do you know why dcache is there?

[MoonlightSentinel]

Removed the revert-... branch, that was a remant of the recent CI debugging.

[maxhaton]

The newCTFE branch may be seeing some use within the next few days