Update pubspec.yaml (#24)

diff --git a/pubspec.yaml b/pubspec.yaml
index a8a5ef8..93d15ea 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -1,10 +1,10 @@
 name: sync_http
-version: 0.3.0
+version: 0.3.1-dev
 description: Synchronous HTTP client for Dart.
-homepage: https://github.com/dart-lang/sync_http
+homepage: https://github.com/google/sync_http.dart
 
 environment:
-  sdk: '>=2.12.0-0 <3.0.0'
+  sdk: '>=2.12.0 <3.0.0'
 
 dev_dependencies:
   pedantic: ^1.10.0-nullsafety.0