patch 8.2.3276: Vim9: exists() can only be evaluated at runtime

Problem:    Vim9: exists() can only be evaluated at runtime.
Solution:   Evaluate at compile time for option name literals. (closes #8437)
diff --git a/src/version.c b/src/version.c
index fae2fd6..8798002 100644
--- a/src/version.c
+++ b/src/version.c
@@ -756,6 +756,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    3276,
+/**/
     3275,
 /**/
     3274,