[clang-tools-extra] [clang-tidy] Fix crash in modernize-use-designated-initializers check (PR #113688)

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z1nke wrote:

Hi, I don’t have write access to merge code, and this is my first commit to clang-tidy. What else needs to be done to merge this PR? Thanks!

https://github.com/llvm/llvm-project/pull/113688