fix docker by using PROPOSAL latest

Dockerfile

@@ -19,11 +19,15 @@ RUN   cd /opt && \
 
 ADD . /km3buu
 
-RUN cd /km3buu && \
-    pip3 install --upgrade pip && \
+RUN pip3 install --upgrade pip && \
     pip3 install setuptools-scm && \
-    pip3 install pytest-runner && \
-    pip3 install conan && \
+    pip3 install pytest-runner
+
+RUN cd /opt && \
+    git clone https://github.com/tudo-astroparticlephysics/PROPOSAL.git && cd PROPOSAL && \
+    pip3 install -e .
+
+RUN cd /km3buu && \
     pip3 install -e . && \
     pip3 install -e ".[dev]" && \
     pip3 install -e ".[extras]"