patch 8.2.1550: Vim9: bufname('%') gives an error

Problem:    Vim9: bufname('%') gives an error.
Solution:   Only give an error for wrong argument type. (closes #6807)
diff --git a/src/version.c b/src/version.c
index d4bca78..8e11299 100644
--- a/src/version.c
+++ b/src/version.c
@@ -755,6 +755,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1550,
+/**/
     1549,
 /**/
     1548,