patch 8.1.2162: popup resize test is flaky

Problem:    Popup resize test is flaky. (Christian Brabandt)
Solution:   Add the function to the list of flaky tests.
diff --git a/src/version.c b/src/version.c
index f84340d..347e0d5 100644
--- a/src/version.c
+++ b/src/version.c
@@ -754,6 +754,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    2162,
+/**/
     2161,
 /**/
     2160,