Correct spelling of 'publishing' (#3767)

diff --git a/lib/src/validator/dependency_override.dart b/lib/src/validator/dependency_override.dart
index a16367a..96a0b83 100644
--- a/lib/src/validator/dependency_override.dart
+++ b/lib/src/validator/dependency_override.dart
@@ -24,7 +24,7 @@
 
 This might be necessary for packages with cyclic dependencies.
 
-Please be extra careful when publising.''');
+Please be extra careful when publishing.''');
     }
     return Future.value();
   }