patch 8.1.0428: the :suspend command is not tested

Problem:    The :suspend command is not tested.
Solution:   Add a test. (Dominique Pelle, closes #3472)
diff --git a/src/version.c b/src/version.c
index 88163a2..724c9aa 100644
--- a/src/version.c
+++ b/src/version.c
@@ -795,6 +795,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    428,
+/**/
     427,
 /**/
     426,