[clang-tools-extra] [clang-tidy] Fix false positives in readability-trailing-comma for designated initializers (PR #215934)

[Zeyi Xu via cfe-commits]

zeyi2 wrote:

(This may fail because of the Release Notes, you probably need to manually backport it @nakasan617 )

https://github.com/llvm/llvm-project/pull/215934