[clang-tools-extra] [clang-tools-extra] Turn misc copy-assign to move-assign (PR #184146)

[Nathan Ridge via cfe-commits]

https://github.com/HighCommander4 approved this pull request.

Grammar nit: commit message wording should be "Change ... to ..." or "Turn ... into ...".

https://github.com/llvm/llvm-project/pull/184146