Bump mypy version

Author: domdfcoding

repo_helper.yml

@@ -15,7 +15,6 @@ python_deploy_version: 3.6
 use_whey: true
 min_coverage: 100
 sphinx_html_theme: furo
-mypy_version: "0.910"
 docs_fail_on_warning: true
 
 conda_channels:

tox.ini

@@ -102,7 +102,7 @@ basepython = python3.6
 ignore_errors = True
 changedir = {toxinidir}
 deps =
-    mypy==0.910
+    mypy==0.931
     -r{toxinidir}/tests/requirements.txt
 commands = mypy flake8_slots tests {posargs}