style: drop redundant comments and apply formatting

Frontend now uses double quotes and semicolons. No behaviour change.

backend/tests/test_auth.py

@@ -70,7 +70,7 @@ class AuthTests(ApiTestCase):
 
     def test_login_is_case_insensitive_on_username(self):
         self.register("Alice")
-        self.client = app.test_client()  # fresh cookie jar: signed out
+        self.client = app.test_client()
         response = self.call(
             "POST",
             "/api/auth/login",
@@ -116,9 +116,7 @@ class AuthTests(ApiTestCase):
         self.register()
         token = self.session_token()
         self.assertEqual(self.call("POST", "/api/auth/logout").status_code, 204)
-        self.client.set_cookie(
-            "sid", token, domain="localhost", path="/api"
-        )  # replay the stolen cookie
+        self.client.set_cookie("sid", token, domain="localhost", path="/api")
         self.assertEqual(self.call("GET", "/api/auth/me").status_code, 401)
 
     def test_idle_session_expires(self):