Avoid race condition when removing cache file

[eschnett]

No description provided.

[eschnett]

This addresses #14118 .

[tkelman]

I think there's technically a chance that rm could throw something other than a ENOENT, in which case this would mask #12720. This probably calls for either a fancier catch that checks the exception type, or a force keyword argument that ignores nonexistent files.

[eschnett]

See #14248.

[tkelman]

Great. I don't think I want to backport this version, unless it gets changed to add more of the checking of exceptions that you're putting into the force kwarg.