[clang-tools-extra] [clang-tidy] Add `readability-redundant-zero-initializer` (PR #209367)

[Baranov Victor via cfe-commits]

https://github.com/vbvictor commented:

Stylistically LGTM, only couple nits.
Semantically I trust others so LGTM if everyone else is happy.

https://github.com/llvm/llvm-project/pull/209367