Fix typo in intl.dart doc.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=138810464
diff --git a/lib/intl.dart b/lib/intl.dart
index 29b78ff..46298b7 100644
--- a/lib/intl.dart
+++ b/lib/intl.dart
@@ -140,7 +140,7 @@
   ///
   /// The [args] repeats the arguments of the enclosing
   /// function, [desc] provides a description of usage,
-  /// [examples] is a Map of exmaples for each interpolated variable.
+  /// [examples] is a Map of examples for each interpolated variable.
   /// For example
   ///
   ///       hello(yourName) => Intl.message(