Revert "Update SnackBar to support Material 3" (#116199)

* Revert "Update SnackBar to support Material 3 (#115750)"

This reverts commit d58855c.

* Kick ci.yaml

Co-authored-by: Jenn Magder <magder@google.com>

Author: Piinks

dev/tools/gen_defaults/bin/gen_defaults.dart

@@ -44,7 +44,6 @@ import 'package:gen_defaults/progress_indicator_template.dart';
 import 'package:gen_defaults/radio_template.dart';
 import 'package:gen_defaults/segmented_button_template.dart';
 import 'package:gen_defaults/slider_template.dart';
-import 'package:gen_defaults/snackbar_template.dart';
 import 'package:gen_defaults/surface_tint.dart';
 import 'package:gen_defaults/switch_template.dart';
 import 'package:gen_defaults/text_field_template.dart';
@@ -162,7 +161,6 @@ Future<void> main(List<String> args) async {
   ProgressIndicatorTemplate('ProgressIndicator', '$materialLib/progress_indicator.dart', tokens).updateFile();
   RadioTemplate('Radio<T>', '$materialLib/radio.dart', tokens).updateFile();
   SegmentedButtonTemplate('SegmentedButton', '$materialLib/segmented_button.dart', tokens).updateFile();
-  SnackbarTemplate('md.comp.snackbar', 'Snackbar', '$materialLib/snack_bar.dart', tokens).updateFile();
   SliderTemplate('md.comp.slider', 'Slider', '$materialLib/slider.dart', tokens).updateFile();
   SurfaceTintTemplate('SurfaceTint', '$materialLib/elevation_overlay.dart', tokens).updateFile();
   SwitchTemplate('Switch', '$materialLib/switch.dart', tokens).updateFile();