patch 8.2.2414: using freed memory when closing the cmdline window

Problem:    Using freed memory when closing the cmdline window.
Solution:   Check the window is still valid.
diff --git a/src/version.c b/src/version.c
index c95b106..071a36e 100644
--- a/src/version.c
+++ b/src/version.c
@@ -751,6 +751,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    2414,
+/**/
     2413,
 /**/
     2412,