patch 8.2.1013: channel tests can be a bit flaky

Problem:    Channel tests can be a bit flaky.
Solution:   Set the g:test_is_flaky flag in SetUp().
diff --git a/src/version.c b/src/version.c
index 9fc5670..4cc8261 100644
--- a/src/version.c
+++ b/src/version.c
@@ -755,6 +755,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1013,
+/**/
     1012,
 /**/
     1011,