patch 8.2.1261: Vim9: common type of function not tested

Problem:    Vim9: common type of function not tested.
Solution:   Add a test.  Fix uncovered problems.
diff --git a/src/version.c b/src/version.c
index 8df1359..a779d54 100644
--- a/src/version.c
+++ b/src/version.c
@@ -755,6 +755,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1261,
+/**/
     1260,
 /**/
     1259,