MAINT: removed unnecessary dependency (docker-compose)

.docker/Dockerfile

 FROM debian:latest
 RUN apt-get update && \
 	 apt-get install tox curl python3-pip git python-autopep8 -y
-RUN pip3 install docker-compose
 COPY .docker/wait-for-it.sh /wait-for-it.sh
 RUN git clone https://gitlab.gwdg.de/bmp-caosdb/caosdb-pylib.git && \
    cd caosdb-pylib && pip3 install .