patch 8.1.0099: exclamation mark in error message not needed

Problem:    Exclamation mark in error message not needed.
Solution:   Remove the exclamation mark.
diff --git a/src/version.c b/src/version.c
index 5cf6882..23b7246 100644
--- a/src/version.c
+++ b/src/version.c
@@ -762,6 +762,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    99,
+/**/
     98,
 /**/
     97,