[android_alarm_manager] Bump version for NNBD stable (#3608)

diff --git a/packages/android_alarm_manager/CHANGELOG.md b/packages/android_alarm_manager/CHANGELOG.md
index b06f23c..10ad02a 100644
--- a/packages/android_alarm_manager/CHANGELOG.md
+++ b/packages/android_alarm_manager/CHANGELOG.md
@@ -1,4 +1,4 @@
-##  2.0.0-nullsafety
+##  2.0.0
 
 * Migrate to null safety.
 
diff --git a/packages/android_alarm_manager/example/pubspec.yaml b/packages/android_alarm_manager/example/pubspec.yaml
index 029a604..b92f45c 100644
--- a/packages/android_alarm_manager/example/pubspec.yaml
+++ b/packages/android_alarm_manager/example/pubspec.yaml
@@ -11,10 +11,10 @@
     # The example app is bundled with the plugin so we use a path dependency on
     # the parent directory to use the current plugin's version.
     path: ../
-  shared_preferences: ^2.0.0-nullsafety
+  shared_preferences: ^2.0.0
   integration_test:
     path: ../../integration_test
-  path_provider: ^2.0.0-nullsafety
+  path_provider: ^2.0.0
 
 dev_dependencies:
   espresso: ^0.0.1+3
@@ -22,11 +22,11 @@
     sdk: flutter
   flutter_test:
     sdk: flutter
-  pedantic: ^1.8.0
+  pedantic: ^1.10.0
 
 flutter:
   uses-material-design: true
 
 environment:
-  sdk: '>=2.12.0-0 <3.0.0'
-  flutter: ">=1.12.13+hotfix.5"
+  sdk: '>=2.12.0-259.9.beta <3.0.0'
+  flutter: ">=1.20.0"
diff --git a/packages/android_alarm_manager/pubspec.yaml b/packages/android_alarm_manager/pubspec.yaml
index ab19372..3934de6 100644
--- a/packages/android_alarm_manager/pubspec.yaml
+++ b/packages/android_alarm_manager/pubspec.yaml
@@ -1,7 +1,7 @@
 name: android_alarm_manager
 description: Flutter plugin for accessing the Android AlarmManager service, and
   running Dart code in the background when alarms fire.
-version: 2.0.0-nullsafety
+version: 2.0.0
 homepage: https://github.com/flutter/plugins/tree/master/packages/android_alarm_manager
 
 dependencies:
@@ -11,7 +11,7 @@
 dev_dependencies:
   flutter_test:
     sdk: flutter
-  pedantic: ^1.8.0
+  pedantic: ^1.10.0
 
 flutter:
   plugin:
@@ -21,5 +21,5 @@
         pluginClass: AndroidAlarmManagerPlugin
 
 environment:
-  sdk: '>=2.12.0-0 <3.0.0'
-  flutter: ">=1.12.13+hotfix.5"
+  sdk: '>=2.12.0-259.9.beta <3.0.0'
+  flutter: ">=1.20.0"