[clang-tools-extra] [clang-tidy] Add new check bugprone-tagged-union-member-count (PR #89925)

[Piotr Zegar via cfe-commits]

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@@ -142,6 +142,7 @@ Clang-Tidy Checks
    :doc:`bugprone-suspicious-stringview-data-usage <bugprone/suspicious-stringview-data-usage>`,
    :doc:`bugprone-swapped-arguments <bugprone/swapped-arguments>`, "Yes"
    :doc:`bugprone-switch-missing-default-case <bugprone/switch-missing-default-case>`,
+   :doc:`bugprone-tagged-union-member-count <bugprone/tagged-union-member-count>`, "Yes"
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PiotrZSL wrote:

check does not provide fixes, so remove `"Yes"`

https://github.com/llvm/llvm-project/pull/89925