Bump flask from 0.12.4 to 1.0

Bumps [flask](https://github.com/pallets/flask) from 0.12.4 to 1.0.
- [Release notes](https://github.com/pallets/flask/releases)
- [Changelog](https://github.com/pallets/flask/blob/master/CHANGES.rst)
- [Commits](pallets/flask@0.12.4...1.0)

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

setup.py

@@ -34,7 +34,7 @@
         # also loosened to use the debian package
         'gevent >=1.0',
         'gevent-websocket==0.9.3',
-        'flask==0.12.4',
+        'flask==1.0',
         'websocket-client==0.12.0',
         'python-dateutil',
         'pytz'