abg-tools-utils: Fix comment

	* include/abg-tools-utils.h (enum abidiff_status): Fix a comment.

Signed-off-by: Dodji Seketeli <dodji@redhat.com>
diff --git a/include/abg-tools-utils.h b/include/abg-tools-utils.h
index 12651fc..dc62b3f 100644
--- a/include/abg-tools-utils.h
+++ b/include/abg-tools-utils.h
@@ -222,7 +222,7 @@
   /// Its numerical value is 0.
   ABIDIFF_OK = 0,
 
-  /// This bit is set if there an application error.
+  /// This bit is set if there is an application error.
   ///
   /// Its numerical value is 1.
   ABIDIFF_ERROR = 1,