fix google_maps_flutter_platform_interface version (#3500)

diff --git a/packages/google_maps_flutter/google_maps_flutter_platform_interface/pubspec.yaml b/packages/google_maps_flutter/google_maps_flutter_platform_interface/pubspec.yaml
index d8b260a..487a54b 100644
--- a/packages/google_maps_flutter/google_maps_flutter_platform_interface/pubspec.yaml
+++ b/packages/google_maps_flutter/google_maps_flutter_platform_interface/pubspec.yaml
@@ -3,7 +3,7 @@
 homepage: https://github.com/flutter/plugins/tree/master/packages/google_maps_flutter/google_maps_flutter_platform_interface
 # NOTE: We strongly prefer non-breaking changes, even at the expense of a
 # less-clean API. See https://flutter.dev/go/platform-interface-breaking-changes
-version: 1.1.0
+version: 1.2.0
 
 dependencies:
   flutter: