patch 8.1.2180: Error E303 is not useful when 'directory' is empty

Problem:    Error E303 is not useful when 'directory' is empty.
Solution:   Skip the error message. (Daniel Hahler, #5067)
diff --git a/src/version.c b/src/version.c
index 38f8277..aebadab 100644
--- a/src/version.c
+++ b/src/version.c
@@ -742,6 +742,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    2180,
+/**/
     2179,
 /**/
     2178,