fixup! Update vendored zlib library

Author: HexDecimal

build_libtcod.py

@@ -162,7 +162,7 @@ def walk_sources(directory: str) -> Iterator[str]:
 
 libraries: list[str] = [*build_sdl.libraries]
 library_dirs: list[str] = [*build_sdl.library_dirs]
-define_macros: list[tuple[str, Any]] = []  # [("Py_LIMITED_API", Py_LIMITED_API)]
+define_macros: list[tuple[str, Any]] = [("Z_SOLO", None)]  # [("Py_LIMITED_API", Py_LIMITED_API)]
 
 sources += walk_sources("tcod/")
 sources += walk_sources("libtcod/src/libtcod/")