Update LICENSE

one more fix
diff --git a/LICENSE b/LICENSE
index c89e88b..162572a 100644
--- a/LICENSE
+++ b/LICENSE
@@ -1,4 +1,4 @@
-Copyright 2014, the Dart project authors. A
+Copyright 2014, the Dart project authors.
 
 Redistribution and use in source and binary forms, with or without
 modification, are permitted provided that the following conditions are