[clang] [clang] Allow parentheses around CTAD declarators (PR #132829)

[via cfe-commits]

cor3ntin wrote:

> CC @Endilll Should this also add a test to [cwg23xx.cpp](https://github.com/llvm/llvm-project/blob/main/clang/test/CXX/drs/cwg23xx.cpp)?

Yes, please!

https://github.com/llvm/llvm-project/pull/132829