Remove Setuptools obsolete zip_safe flag (#9758)

Author: hugovk

setup.py

@@ -1065,10 +1065,6 @@ def summary_report(self, feature: ext_feature) -> None:
         print("")
 
 
-def debug_build() -> bool:
-    return hasattr(sys, "gettotalrefcount") or FUZZING_BUILD
-
-
 libraries: list[tuple[str, _BuildInfo]] = [
     ("pil_imaging_mode", {"sources": ["src/libImaging/Mode.c"]}),
 ]
@@ -1099,7 +1095,6 @@ def debug_build() -> bool:
         cmdclass={"build_ext": pil_build_ext},
         ext_modules=ext_modules,
         libraries=libraries,
-        zip_safe=not (debug_build() or PLATFORM_MINGW),
     )
 except RequiredDependencyException as err:
     msg = f"""