Bump geoalchemy2 from 0.8.3 to 0.8.4

Bumps [geoalchemy2](https://github.com/geoalchemy/geoalchemy2) from 0.8.3 to 0.8.4.
- [Release notes](https://github.com/geoalchemy/geoalchemy2/releases)
- [Changelog](https://github.com/geoalchemy/geoalchemy2/blob/master/CHANGES.txt)
- [Commits](https://github.com/geoalchemy/geoalchemy2/compare/0.8.3...0.8.4)

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

setup.py

@@ -42,7 +42,7 @@ setup(
         'celery==4.4.5',
         'redis==3.5.3',
         'aerofiles==1.0.0',
-        'geoalchemy2==0.8.3',
+        'geoalchemy2==0.8.4',
         'shapely==1.7.0',
         'ogn-client==0.9.7',
         'psycopg2-binary==2.8.5',