[clang] [clang-tools-extra] [clang-tidy] New performance linter: performance-inefficient-copy-assign (PR #179467)

[Baranov Victor via cfe-commits]

vbvictor wrote:

Some previous PR's with same check:
https://github.com/llvm/llvm-project/pull/139525
https://reviews.llvm.org/D137205

cc @Febbe as you had approach with CFG before.

https://github.com/llvm/llvm-project/pull/179467