patch 9.0.1213: adding a line below the last one does not expand fold

Problem:    Adding a line below the last one does not expand fold.
Solution:   Do not skip mark_adjust() when adding lines below the last one.
            (Brandon Simmons, closes #11832, closes #10698)
diff --git a/src/version.c b/src/version.c
index 3496b3a..ae5de35 100644
--- a/src/version.c
+++ b/src/version.c
@@ -696,6 +696,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1213,
+/**/
     1212,
 /**/
     1211,