The Messenger: Make modules and tests PEP8 (#2276)

* The Messenger: PEP8 module and test names

* fix dumb

* whitespace

worlds/messenger/test/test_locations.py

@@ -0,0 +1,16 @@
+from . import MessengerTestBase
+from ..subclasses import MessengerLocation
+
+
+class LocationsTest(MessengerTestBase):
+    options = {
+        "shuffle_shards": "true",
+    }
+
+    @property
+    def run_default_tests(self) -> bool:
+        return False
+
+    def test_locations_exist(self) -> None:
+        for location in self.multiworld.worlds[1].location_name_to_id:
+            self.assertIsInstance(self.multiworld.get_location(location, self.player), MessengerLocation)