patch 8.1.0691: text properties are not adjusted for :substitute

Problem:    Text properties are not adjusted for :substitute.
Solution:   Adjust text properties as well as possible.
diff --git a/src/version.c b/src/version.c
index 8e14a2e..144c9ef 100644
--- a/src/version.c
+++ b/src/version.c
@@ -800,6 +800,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    691,
+/**/
     690,
 /**/
     689,