Rollup merge of #139948 - jieyouxu:ignore-breakup-commit, r=onur-ozkan

git: ignore `60600a6fa403216bfd66e04f948b1822f6450af7` for blame purposes

60600a6 was simply breaking up compiletest's `runtest.rs` and isn't very useful in git blame.

r? `@onur-ozkan`

Author: matthiaskrgr