Bump flask-cors from 3.0.8 to 3.0.9

Bumps [flask-cors](https://github.com/corydolphin/flask-cors) from 3.0.8 to 3.0.9.
- [Release notes](https://github.com/corydolphin/flask-cors/releases)
- [Changelog](https://github.com/corydolphin/flask-cors/blob/master/CHANGELOG.md)
- [Commits](corydolphin/flask-cors@3.0.8...3.0.9)

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

requirements.txt

@@ -2,7 +2,7 @@ arrow==0.10.0
 eventbrite==3.3.3
 flake8==3.7.8
 Flask==1.1.1
-Flask-Cors==3.0.8
+Flask-Cors==3.0.9
 gunicorn==19.9.0
 pylint==2.4.3
 python-box==3.4.5