patch 9.0.0856: MS-Windows: executable not found when running test

Problem:    MS-Windows: executable not found when running individual test.
Solution:   Also look for vimd.exe. (Christopher Plewright, closes #11525)
diff --git a/src/version.c b/src/version.c
index acade23..50f6709 100644
--- a/src/version.c
+++ b/src/version.c
@@ -696,6 +696,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    856,
+/**/
     855,
 /**/
     854,