patch 9.1.0156: Make 'wfb' failing to split still report E1513

Problem:  may not be clear why failing to split causes an ":Xdo" command
          to abort if 'wfb' is set.
Solution: do not return immediately if win_split fails, so E1513 is
          still given. Expect both errors in the test. Also fix tests to
          pass CI.
          (Sean Dewar)

closes: #14152

Signed-off-by: Sean Dewar <6256228+seandewar@users.noreply.github.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/src/version.c b/src/version.c
index f1af6cb..03ad6fe 100644
--- a/src/version.c
+++ b/src/version.c
@@ -705,6 +705,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    156,
+/**/
     155,
 /**/
     154,