patch 8.2.4771: Coverity warns for not checking return value

Problem:    Coverity warns for not checking return value.
Solution:   Check return value of rettv_dict_alloc().
diff --git a/src/version.c b/src/version.c
index 90b0b12..c5ac7c5 100644
--- a/src/version.c
+++ b/src/version.c
@@ -747,6 +747,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    4771,
+/**/
     4770,
 /**/
     4769,