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-preview[bot] <support@dependabot.com>

requirements.txt

@@ -13,7 +13,7 @@ Flask==1.1.2
 Flask-SQLAlchemy==2.4.4
 Flask-Mail==0.9.1
 Flask-Migrate==2.5.3
-Flask-Cors==3.0.8
+Flask-Cors==3.0.9
 Flask-Babel==1.0.0
 flask-talisman==0.7.0
 SQLAlchemy==1.3.19