chore(deps): bump the json_annotation group

Bumps the json_annotation group in /packages/aws_common with 4 updates: [json_annotation](https://github.com/google/json_serializable.dart), [json_serializable](https://github.com/google/json_serializable.dart), [built_value_generator](https://github.com/google/built_value.dart) and [built_value](https://github.com/google/built_value.dart).


Updates `json_annotation` from 4.8.1 to 4.9.0
- [Release notes](https://github.com/google/json_serializable.dart/releases)
- [Commits](google/json_serializable.dart@json_annotation-v4.8.1...json_annotation-v4.9.0)

Updates `json_serializable` from 6.7.1 to 6.8.0
- [Release notes](https://github.com/google/json_serializable.dart/releases)
- [Commits](google/json_serializable.dart@json_serializable-v6.7.1...json_serializable-v6.8.0)

Updates `built_value_generator` from 8.8.1 to 8.9.2
- [Release notes](https://github.com/google/built_value.dart/releases)
- [Changelog](https://github.com/google/built_value.dart/blob/master/CHANGELOG.md)
- [Commits](https://github.com/google/built_value.dart/commits/v8.9.2)

Updates `built_value` from 8.8.1 to 8.9.2
- [Release notes](https://github.com/google/built_value.dart/releases)
- [Changelog](https://github.com/google/built_value.dart/blob/master/CHANGELOG.md)
- [Commits](https://github.com/google/built_value.dart/commits/v8.9.2)

---
updated-dependencies:
- dependency-name: json_annotation
  dependency-type: direct:production
  update-type: version-update:semver-minor
  dependency-group: json_annotation
- dependency-name: json_serializable
  dependency-type: direct:production
  update-type: version-update:semver-minor
  dependency-group: json_annotation
- dependency-name: built_value_generator
  dependency-type: direct:production
  update-type: version-update:semver-minor
  dependency-group: json_annotation
- dependency-name: built_value
  dependency-type: direct:production
  update-type: version-update:semver-minor
  dependency-group: json_annotation
...

Signed-off-by: dependabot[bot] <support@github.com>

packages/aws_common/pubspec.yaml

@@ -15,7 +15,7 @@ dependencies:
   collection: ^1.15.0
   http2: ^2.0.0
   js: ">=0.6.4 <0.8.0"
-  json_annotation: ">=4.8.1 <4.9.0"
+  json_annotation: ^4.8.1
   logging: ^1.0.0
   meta: ^1.7.0
   mime: ^1.0.0
@@ -29,7 +29,7 @@ dev_dependencies:
   build_runner: ^2.4.0
   build_test: ^2.1.5
   build_web_compilers: ^4.0.0
-  built_value_generator: 8.8.1
-  json_serializable: 6.7.1
+  built_value_generator: 8.9.2
+  json_serializable: 6.8.0
   stream_channel: ^2.1.0
   test: ^1.22.1