Bump pyyaml from 4.2b4 to 5.4 in /docker/meta-low-zoom-batch

Bumps [pyyaml](https://github.com/yaml/pyyaml) from 4.2b4 to 5.4.
- [Release notes](https://github.com/yaml/pyyaml/releases)
- [Changelog](https://github.com/yaml/pyyaml/blob/master/CHANGES)
- [Commits](https://github.com/yaml/pyyaml/commits/5.4)

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

Author: dependabot[bot]

docker/meta-low-zoom-batch/requirements.txt

@@ -13,7 +13,7 @@ pyclipper==1.0.6
 pycountry==17.9.23
 pyproj==2.1.0
 python-dateutil==2.6.1
-PyYAML==4.2b4
+PyYAML==5.4
 redis==2.10.6
 requests==2.20.1
 Shapely==1.6.2.post1