fix: default sync --express to false, add to sync help

Default express to false for sync (same as deploy) until public
announcement. Added TODO to flip default after announcement.
Also add express to sync help text grouping.

Author: roger-zhangg

samcli/commands/sync/command.py

@@ -163,11 +163,12 @@
 )
 @click.option(
     "--express/--no-express",
-    default=True,
+    default=False,
     required=False,
     is_flag=True,
+    # TODO: Flip default to True after public announcement of express mode support
     help="Use CloudFormation Express mode to speed up infrastructure deployments by completing once resource "
-    "configuration is applied, without waiting for full stabilization. Enabled by default.",
+    "configuration is applied, without waiting for full stabilization.",
 )
 @container_env_var_file_option(cls=ContainerOptions)
 @watch_exclude_option
@@ -307,7 +308,7 @@ def do_cli(
     build_in_source: Optional[bool],
     watch_exclude: Optional[Dict[str, List[str]]],
     language_extensions: Optional[bool],
-    express: bool = True,
+    express: bool = False,
 ) -> None:
     """
     Implementation of the ``cli`` method

samcli/commands/sync/core/options.py

@@ -35,6 +35,7 @@
 ADDITIONAL_OPTIONS: List[str] = [
     "watch",
     "code",
+    "express",
     "skip_deploy_sync",
     "dependency_layer",
     "use_container",

tests/unit/commands/sync/test_command.py

@@ -223,7 +223,7 @@ def test_infra_must_succeed_sync(
             on_failure=None,
             max_wait_duration=60,
             language_extensions=None,
-            express=True,
+            express=False,
         )
 
         execute_infra_mock.assert_called_with(
@@ -392,7 +392,7 @@ def test_watch_must_succeed_sync(
             on_failure=None,
             max_wait_duration=60,
             language_extensions=None,
-            express=True,
+            express=False,
         )
         execute_watch_mock.assert_called_once_with(
             template=self.template_file,