run tests on otp23

Author: lukaszsamson

.travis.yml

@@ -30,10 +30,10 @@ matrix:
       elixir: 1.7.4
     - otp_release: 21.3
       elixir: 1.8.2
-    - otp_release: 22.0
+    - otp_release: 22.3
       elixir: 1.9.4
-    - otp_release: 22.2
-      elixir: 1.10.2
+    - otp_release: 23.0
+      elixir: 1.10.3
       env:
         - CHECK_FORMATTED=1
         - RUN_DIALYZER=1