gitconfig color.ui = always breaks patches

[Blaisorblade]

With git's color.ui set to always, I get the following errors:

[ERROR] Could not update repository "bb-overlay-fork": "/usr/local/bin/patch -p1 -i /Users/pgiarrusso/.opam/log/processed-patch-58446-70a526" exited with code 2 "/usr/local/bin/patch: **** Only garbage was found in the patch input."
[bb-overlay] synchronised from git+https://github.com/Blaisorblade/opam-overlay.git
[ERROR] Could not update repository "bb-overlay": "/usr/local/bin/patch -p1 -i /Users/pgiarrusso/.opam/log/processed-patch-58446-e80101" exited with code 2 "/usr/local/bin/patch: **** Only garbage was found in the patch input."
[iris-dev] synchronised from git+https://gitlab.mpi-sws.org/iris/opam.git
[ERROR] Could not update repository "iris-dev": "/usr/local/bin/patch -p1 -i /Users/pgiarrusso/.opam/log/processed-patch-58446-8b8e2c" exited with code 2 "/usr/local/bin/patch: **** Only garbage was found in the patch input."

Maybe opam needs to override color.ui git settings, like it does (IIRC) for a few others (e.g. #3788)?

Tested on opam 2.0.8.

[rjbou]

Can you check that #4884 fixes the issue?