[PATCH] test: fix flaky fails of box/iproto_stress

[Alexander Turenko]

Fixes #3911.
---

https://github.com/tarantool/tarantool/issues/3911
https://github.com/tarantool/tarantool/tree/Totktonada/gh-3911-fix-box-iproto-stress

 test/box/iproto_stress.result   | 1 +
 test/box/iproto_stress.test.lua | 1 +
 2 files changed, 2 insertions(+)

diff --git a/test/box/iproto_stress.result b/test/box/iproto_stress.result
index 4239b49b8..4b7b41bd7 100644
--- a/test/box/iproto_stress.result
+++ b/test/box/iproto_stress.result
@@ -40,6 +40,7 @@ function worker(i)
             n_errors = n_errors + 1
             break
         end
+        conn:wait_state('active', 10)
         for k = 1,10 do
             conn.space.test:insert{i, j, k}
         end
diff --git a/test/box/iproto_stress.test.lua b/test/box/iproto_stress.test.lua
index 2f3071450..84a58641f 100644
--- a/test/box/iproto_stress.test.lua
+++ b/test/box/iproto_stress.test.lua
@@ -23,6 +23,7 @@ function worker(i)
             n_errors = n_errors + 1
             break
         end
+        conn:wait_state('active', 10)
         for k = 1,10 do
             conn.space.test:insert{i, j, k}
         end
-- 
2.20.0