patch 8.2.0540: regexp and other code not tested

Problem:    Regexp and other code not tested.
Solution:   Add more tests. (Yegappan Lakshmanan, closes #5904)
diff --git a/src/version.c b/src/version.c
index 2bba57d..be24594 100644
--- a/src/version.c
+++ b/src/version.c
@@ -739,6 +739,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    540,
+/**/
     539,
 /**/
     538,