4a23553b83
`StringRefNull ` expects a null terminated string and `StringRefNull (const char *)` initializer already realizes a runtime assert to avoid `nullptr` c strings, however this stills allows initializing `StringRefNull ` with a explicit `nullptr`. Deleting `StringRefNull(std::nullptr_t)` gives a error if `StringRefNull` is initialized with a implicit `nullptr`. This follows the same deleted `std::string(std::nullptr_t)` initializer in c++23. Pull Request: https://projects.blender.org/blender/blender/pulls/130935