patch 8.2.1520: Vim9: CTRL-] used in :def function does not work

Problem:    Vim9: CTRL-] used in :def function does not work.
Solution:   Omit count or prepend colon. (closes #6769)
diff --git a/src/normal.c b/src/normal.c
index cb8e736..1ef6509 100644
--- a/src/normal.c
+++ b/src/normal.c
@@ -3644,8 +3644,10 @@
 	    {
 		if (g_cmd)
 		    STRCPY(buf, "tj ");
+		else if (cap->count0 == 0)
+		    STRCPY(buf, "ta ");
 		else
-		    sprintf((char *)buf, "%ldta ", cap->count0);
+		    sprintf((char *)buf, ":%ldta ", cap->count0);
 	    }
     }