mintro: typings again x2

Co-authored-by: Dylan Baker <dylan@pnwbakers.com>

mesonbuild/mintro.py

@@ -53,7 +53,7 @@ class IntroCommand:
 def get_meson_introspection_types(coredata: T.Optional[cdata.CoreData] = None,
                                   builddata: T.Optional[build.Build] = None,
                                   backend: T.Optional[backends.Backend] = None,
-                                  sourcedir: T.Optional[str] = None) -> 'collections.OrderedDict[str, IntroCommand]':
+                                  sourcedir: T.Optional[str] = None) -> 'T.Mapping[str, IntroCommand]':
     if backend and builddata:
         benchmarkdata = backend.create_test_serialisation(builddata.get_benchmarks())
         testdata = backend.create_test_serialisation(builddata.get_tests())