upgrade flutter

.gitignore

@@ -5,9 +5,12 @@
 *.swp
 .DS_Store
 .atom/
+.build/
 .buildlog/
 .history
 .svn/
+.swiftpm/
+migrate_working_dir/
 
 # IntelliJ related
 *.iml
@@ -22,38 +25,24 @@
 
 # Flutter/Dart/Pub related
 **/doc/api/
+**/ios/Flutter/.last_build_id
 .dart_tool/
 .flutter-plugins
 .flutter-plugins-dependencies
-.packages
 .pub-cache/
 .pub/
 /build/
 
-# Web related
-lib/generated_plugin_registrant.dart
-
 # Symbolication related
 app.*.symbols
 
 # Obfuscation related
 app.*.map.json
 
-# Exceptions to above rules.
-!/packages/flutter_tools/test/data/dart_dependencies_test/**/.packages
-android/key.properties
-android/key.jks
-android/app/src/prod/google-services.json
-.gradle/5.6.2/gc.properties
-.gradle/5.6.2/executionHistory/executionHistory.bin
-.gradle/5.6.2/executionHistory/executionHistory.lock
-.gradle/5.6.2/fileChanges/last-build.bin
-.gradle/5.6.2/fileHashes/fileHashes.lock
-.gradle/buildOutputCleanup/buildOutputCleanup.lock
-.gradle/buildOutputCleanup/cache.properties
-.gradle/vcs-1/gc.properties
-android/key.keystore
+# Android Studio will place build artifacts here
+/android/app/debug
+/android/app/profile
+/android/app/release
 android/dev-key.properties
-ios/Runner/GoogleService-Info.plist
+android/app/src/dev/google-services.json
 android/app/google-services.json
-ios/Runner/GoogleService-Info.plist