[smart_holder] Fix `PYBIND11_INTERNALS_SH_DEF` mixup.#5026

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rwgk merged 1 commit intopybind:smart_holderfrom

rwgk:fix_PYBIND11_INTERNALS_SH_DEF_mixup

Feb 20, 2024

Commits on Feb 14, 2024

OMG: `PYBIND11_INTERNALS_SH_DEF` was defined the wrong way around since pybind/pybind11#3283 (merged 2021-09-20).
rwgk
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