Bump geoalchemy2 from 0.4.0 to 0.6.2

Bumps [geoalchemy2](https://github.com/geoalchemy/geoalchemy2) from 0.4.0 to 0.6.2.
- [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/0.4...0.6.2)

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

setup.py

@@ -43,7 +43,7 @@ setup(
         'celery==4.3.0',
 	'redis==3.2.1',
         'aerofiles==1.0.0',
-        'geoalchemy2==0.4.0',
+        'geoalchemy2==0.6.2',
         'shapely==1.6.4.post2',
         'ogn-client==0.9.1',
         'psycopg2-binary==2.8.1',