fix(shorebird_cli): pass flavor when building android artifacts (#628)

packages/shorebird_cli/lib/src/commands/release/release_android_command.dart

@@ -169,6 +169,7 @@ Please bump your version number and try again.''',
       aabPath: bundlePath,
       platform: platform,
       architectures: architectures,
+      flavor: flavor,
     );
 
     logger

packages/shorebird_cli/test/src/commands/release/release_android_command_test.dart

@@ -218,6 +218,7 @@ flutter:
           aabPath: any(named: 'aabPath'),
           platform: any(named: 'platform'),
           architectures: any(named: 'architectures'),
+          flavor: any(named: 'flavor'),
         ),
       ).thenAnswer((_) async {});
       when(() => flutterValidator.validate(any())).thenAnswer((_) async => []);
@@ -457,6 +458,7 @@ flavors:
           platform: platform,
           aabPath: any(named: 'aabPath'),
           architectures: any(named: 'architectures'),
+          flavor: flavor,
         ),
       ).called(1);
       expect(exitCode, ExitCode.success.code);