patch 8.2.2306: Vim9: when using function reference type is not checked

Problem:    Vim9: when using function reference type is not checked.
Solution:   When using a function reference lookup the type and check the
            argument types. (issue #7629)
diff --git a/src/version.c b/src/version.c
index 0e711ed..1945a4a 100644
--- a/src/version.c
+++ b/src/version.c
@@ -751,6 +751,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    2306,
+/**/
     2305,
 /**/
     2304,