patch 8.2.2877: insufficient tests for popup menu rightleft

Problem:    Insufficient tests for popup menu rightleft.
Solution:   Add tests. (Yegappan Lakshmanan, closes #8235)
diff --git a/src/version.c b/src/version.c
index ca18b67..82ecd0a 100644
--- a/src/version.c
+++ b/src/version.c
@@ -751,6 +751,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    2877,
+/**/
     2876,
 /**/
     2875,