patch 8.1.1250: no test for netterm mouse

Problem:    No test for netterm mouse.
Solution:   Add some tests for netterm mouse.
diff --git a/src/version.c b/src/version.c
index 8322aa4..2fee19b 100644
--- a/src/version.c
+++ b/src/version.c
@@ -768,6 +768,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1250,
+/**/
     1249,
 /**/
     1248,