Timeout in `SingleFunctors` on `nightly-testing`

Stream: mathlib4

[Kim Morrison]

Just a heads up to @Joël Riou that singleFunctors in Mathlib/Algebra/Homology/HomotopyCategory/SingleFunctors.lean comes dangerously close to timing out on master (taking over 180,000 heartbeats), and in fact does time out now on nightly-testing.

I've just increased the maxHeartbeats in nightly-testing for now, but if it would be possible to take a look at this and refactor on master (e.g. break out whichever fields are slow), that would be much appreciated.

[Joël Riou]

I have just squeezed simp #13794

[Kim Morrison]

Thanks! :peace_sign: