patch 8.2.1235: Not all mouse codes covered by tests

Problem:    Not all mouse codes covered by tests.
Solution:   Add more tests for the mouse. (Yegappan Lakshmanan, closes #6472)
diff --git a/src/version.c b/src/version.c
index 7a96e58..a65bf1a 100644
--- a/src/version.c
+++ b/src/version.c
@@ -755,6 +755,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1235,
+/**/
     1234,
 /**/
     1233,