install matplotlib to docker image; install cymetric with --no-deps

docker/Dockerfile

@@ -2,11 +2,18 @@ ARG pkg_mgr=apt
 ARG ubuntu_version=22.04
 ARG cycamore_tag=latest
 
-FROM ghcr.io/cyclus/cycamore_${ubuntu_version}_${pkg_mgr}/cycamore:${cycamore_tag} AS cymetric
+FROM ghcr.io/cyclus/cycamore_${ubuntu_version}_${pkg_mgr}/cycamore:${cycamore_tag} AS cycamore-base
 
+FROM cycamore-base AS apt-deps
+RUN apt install -y python3-matplotlib
+
+FROM cycamore-base AS conda-deps
+RUN mamba install -y matplotlib
+
+FROM ${pkg_mgr}-deps AS cymetric
 COPY . /cymetric
 WORKDIR /cymetric
-RUN python3 -m pip install --target $(python3 -m site --user-site) .
+RUN python3 -m pip install --target $(python3 -m site --user-site) --no-deps .
 
 FROM cymetric AS cymetric-pytest
 RUN cd tests && python3 -m pytest