Fix flake8 and isort errors

Note, isort now has default behaviour of searching recursively so we no
longer need the `-rc` flag

app/main/views/two_factor.py

@@ -91,7 +91,7 @@ def revalidate_email_sent():
 
 # see http://flask.pocoo.org/snippets/62/
 def _is_safe_redirect_url(target):
-    from urllib.parse import urlparse, urljoin
+    from urllib.parse import urljoin, urlparse
     host_url = urlparse(request.host_url)
     redirect_url = urlparse(urljoin(request.host_url, target))
     return redirect_url.scheme in ('http', 'https') and \