Support GHC 9.14

[andreasabel]

Blocked on:

• Support for GHC 9.14 phadej/boring#48

Commits:

• Support time-1.15: more direct encoding of unix time 0
  time-1.15 no longer exports its Internal module.
  So use a more direct method to get unix start of epoch.

• Relax upper bounds for GHC 9.14

• Bump Cabal to 3.16

• Bump Haskell-CI to GHC 9.14.1

Closes #1456.

[andreasabel]

Haskell CI for GHC 9.14.1 fails due to dependency:

[__6] rejecting: exceptions-0.10.11/installed-97e4 (conflict: boring => base>=4.12.0.0 && <4.22, exceptions => base==4.22.0.0/installed-8900)

[gbaz]

I'd like to merge but there still seems to be a CI failure about the solver...

[andreasabel]

Yes, we are blocked on boring and for whatever reason @phadej seems to have decided to not drop the bounds that restrict it to GHC <= 9.12.
We don't need boring at all but we are indirectly depending on constraints that also does not need it but exports an instance Boring Dict. I have now launched a PR to get rid of this:

• Support GHC 9.14.1: drop instance Boring dict and dep boring ekmett/constraints#131