patch 8.2.2457: Coverity warns for memory leak

Problem:    Coverity warns for memory leak.
Solution:   Free memory when out of memory.
diff --git a/src/version.c b/src/version.c
index 804899f..ab00e37 100644
--- a/src/version.c
+++ b/src/version.c
@@ -751,6 +751,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    2457,
+/**/
     2456,
 /**/
     2455,