Prepare 2.1.1 release (dart-archive/yaml_edit#52)

Author: jonasfj

pkgs/yaml_edit/CHANGELOG.md

@@ -1,4 +1,4 @@
-## 2.1.1-dev
+## 2.1.1
 
 - Require Dart 2.19
 

pkgs/yaml_edit/pubspec.yaml

@@ -1,8 +1,10 @@
 name: yaml_edit
-version: 2.1.1-dev
+version: 2.1.1
 description: A library for YAML manipulation with comment and whitespace preservation.
 repository: https://github.com/dart-lang/yaml_edit
 issue_tracker: https://github.com/dart-lang/yaml_edit/issues
+topics:
+ - yaml
 
 environment:
   sdk: ">=2.19.0 <3.0.0"