rev to 2.5.0 and prep to publish (#267)

diff --git a/.github/workflows/test-package.yml b/.github/workflows/test-package.yml
index e2ccc15..37e64ac 100644
--- a/.github/workflows/test-package.yml
+++ b/.github/workflows/test-package.yml
@@ -47,7 +47,7 @@
         # Add macos-latest and/or windows-latest if relevant for this package
         os: [ubuntu-latest]
         # Add stable if the package should also be tested on stable
-        sdk: [2.19.0, dev]
+        sdk: ['3.0', dev]
     steps:
       - uses: actions/checkout@9bb56186c3b09b4f86b1c65136769dd318469633
       - uses: dart-lang/setup-dart@fedb1266e91cf51be2fdb382869461a434b920a3
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 6f2b821..cbf7efc 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,7 +1,8 @@
-## 2.5.0-wip
+## 2.5.0
 
 * Introduce new typed `ArgResults` `flag(String)`, `option(String)`, and
   `multiOption(String)` methods.
+* Require Dart 3.0.
 
 ## 2.4.2
 
diff --git a/pubspec.yaml b/pubspec.yaml
index 3acfa3e..40967a6 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -1,5 +1,5 @@
 name: args
-version: 2.5.0-wip
+version: 2.5.0
 description: >-
   Library for defining parsers for parsing raw command-line arguments into a set
   of options and values using GNU and POSIX style options.
@@ -9,7 +9,7 @@
   - cli
 
 environment:
-  sdk: '>=2.19.0 <4.0.0'
+  sdk: ^3.0.0
 
 dev_dependencies:
   dart_flutter_team_lints: ^1.0.0