Cleaned spaces at the end of lines and newlines of end of files

See merge request dynamicexposure/openbuildingmap/the-engine!2

Changed to double quotes according to Docstring Conventions.

See merge request dynamicexposure/openbuildingmap/the-engine!1

needed for coverage report

change DOCKER_HOST\n checkout https://gitlab.com/gitlab-org/charts/gitlab/-/issues/478#note_75907915

Plan is to use the pytest-docker-compose pluging but this refuses to
return after starting the docker container. Thus, for now, we have to
start the container manually.