patch 9.1.0391: Vim9: could improve testing

Problem:  Vim9: could improve testing
          (Ernie Rael)
Solution: Support defcompile for test_override() to
          improve testing (Yegappan Lakshmanan)

fixes: #14553
closes: #14712

Signed-off-by: Yegappan Lakshmanan <yegappan@yahoo.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/src/globals.h b/src/globals.h
index 2c00e5f..fb5c7b3 100644
--- a/src/globals.h
+++ b/src/globals.h
@@ -1936,6 +1936,7 @@
 EXTERN int  disable_vterm_title_for_testing INIT(= FALSE);
 EXTERN long override_sysinfo_uptime INIT(= -1);
 EXTERN int  override_autoload INIT(= FALSE);
+EXTERN int  override_defcompile INIT(= FALSE);
 EXTERN int  ml_get_alloc_lines INIT(= FALSE);
 EXTERN int  ignore_unreachable_code_for_testing INIT(= FALSE);