add dependency "pydocstyle<4"

okue · okue · commit 76aad5b1d2e1 · 2019-07-14T16:17:54.000+09:00
diff --git a/tox.ini b/tox.ini
@@ -19,6 +19,7 @@ deps =
     six
     flake8
     flake8-docstrings
+    pydocstyle<4
 commands = flake8 linebot/
 
 [testenv:py37-flake8-other]
