Remove -dev.infinity in SDK upper constraint
diff --git a/pubspec.yaml b/pubspec.yaml
index 221d92b..d8c2029 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -4,7 +4,7 @@
 description: A library for parsing CSS.
 homepage: https://github.com/dart-lang/csslib
 environment:
-  sdk: '>=1.21.0 <2.0.0-dev.infinity'
+  sdk: '>=1.21.0 <2.0.0'
 dependencies:
   args: '>=0.9.0 <0.14.0'
   logging: '>=0.9.0 <0.12.0'