patch 8.2.3933: after ":cd" fails ":cd -" is incorrect

Problem:    After ":cd" fails ":cd -" is incorrect.
Solution:   Set the previous directory only after successfully changing
            directory. (Richard Doty, closes #9419, closes #8983)
diff --git a/src/version.c b/src/version.c
index bbfa0ff..2b1ce02 100644
--- a/src/version.c
+++ b/src/version.c
@@ -750,6 +750,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    3933,
+/**/
     3932,
 /**/
     3931,