Rollup merge of #149107 - Enselic:option-inspect-mutation, r=jieyouxu

rustc_borrowck: Don't suggest changing closure param type not under user control

This changes output of a handful of tests more than the one added in the first commit, but as far as I can tell, all removed suggestions were invalid.

Closes rust-lang/rust#128381 which is **D-invalid-suggestion** with two 👍-votes.

Author: Zalathar