patch 8.2.1356: Vim9: cannot get the percent register

Problem:    Vim9: cannot get the percent register.
Solution:   Check for readable registers instead of writable. (closes #6566)
diff --git a/src/version.c b/src/version.c
index c27c94a..b04f4fe 100644
--- a/src/version.c
+++ b/src/version.c
@@ -755,6 +755,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1356,
+/**/
     1355,
 /**/
     1354,