[clang-tools-extra] [llvm] [GitHub] Bump clang-tidy version to 21th in CI (PR #160193)

[via llvm-commits]

github-actions[bot] wrote:

<!--LLVM CODE LINT COMMENT: clang-tidy-->


:warning: C/C++ code linter clang-tidy found issues in your code. :warning:

<details>
<summary>
You can test this locally with the following command:
</summary>

```bash

git diff -U0 origin/main...HEAD -- clang-tools-extra/clang-tidy/ClangTidy.cpp |
python3 clang-tools-extra/clang-tidy/tool/clang-tidy-diff.py \
  -path build -p1 -quiet
```

</details>

<details>
<summary>
View the output from clang-tidy here.
</summary>

```
clang-tools-extra/clang-tidy/ClangTidy.cpp:269:8: warning: invalid case style for function 'ReportFix' [readability-identifier-naming]
  185 |   void ReportFix(const DiagnosticBuilder &Diag,
      |        ^~~~~~~~~
      |        reportFix
```

</details>


https://github.com/llvm/llvm-project/pull/160193