Add missing methods to ExtensionFileLoader (#6120)

Closes: #4769

stdlib/importlib/machinery.pyi

@@ -115,3 +115,7 @@ class ExtensionFileLoader(importlib.abc.ExecutionLoader):
     def __init__(self, name: str, path: importlib.abc._Path) -> None: ...
     def get_filename(self, name: str | None = ...) -> importlib.abc._Path: ...
     def get_source(self, fullname: str) -> None: ...
+    def create_module(self, spec: ModuleSpec) -> types.ModuleType: ...
+    def exec_module(self, module: types.ModuleType) -> None: ...
+    def is_package(self, fullname: str) -> bool: ...
+    def get_code(self, fullname: str) -> None: ...