patch 8.2.2290: Vim9: unlet of global variable cannot be compiled

Problem:    Vim9: unlet of global variable cannot be compiled.
Solution:   Skip over variables that might be defined later. Give an error if
            a subscript is found. (closes #7585)
diff --git a/src/version.c b/src/version.c
index c5017a4..5585365 100644
--- a/src/version.c
+++ b/src/version.c
@@ -751,6 +751,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    2290,
+/**/
     2289,
 /**/
     2288,