type_caster_generic: fix compiler error when casting a T that is implicitly convertible from T* (#5873)

* type_caster_generic: fix compiler error when casting a T that is implicitly convertible from T*

* style: pre-commit fixes

* Placate clang-tidy

* Expand NOLINT to specify Clang-Tidy check names

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Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Co-authored-by: Ralf W. Grosse-Kunstleve <rgrossekunst@nvidia.com>
2 files changed