patch 8.2.1554: crash in normal test

Problem:    Crash in normal test.
Solution:   Skip adjusting marks if there are no folds.

src/fold.c

@@ -1515,6 +1515,9 @@ foldMarkAdjustRecurse(
     linenr_T	last;
     linenr_T	top;
 
+    if (gap->ga_len == 0)
+	return;
+
     // In Insert mode an inserted line at the top of a fold is considered part
     // of the fold, otherwise it isn't.
     if ((State & INSERT) && amount == (linenr_T)1 && line2 == MAXLNUM)

src/version.c

@@ -754,6 +754,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1554,
 /**/
     1553,
 /**/