patch 8.0.0593: duplication of code for adding a list or dict return value

Problem:    Duplication of code for adding a list or dict return value.
Solution:   Add rettv_dict_set() and rettv_list_set(). (Yegappan Lakshmanan)
diff --git a/src/version.c b/src/version.c
index fb0d9a5..9e6eeac 100644
--- a/src/version.c
+++ b/src/version.c
@@ -765,6 +765,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    593,
+/**/
     592,
 /**/
     591,