patch 8.1.0398: no test for -o and -O command line arguments

Problem:    No test for -o and -O command line arguments.
Solution:   Add a test. (Dominique Pelle, closes #3438)
diff --git a/src/version.c b/src/version.c
index 726e102..adde06a 100644
--- a/src/version.c
+++ b/src/version.c
@@ -795,6 +795,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    398,
+/**/
     397,
 /**/
     396,