Move back to using pypi pynbody

Now that linux aarch64 wheels are available, this should work

genetIC/Dockerfile

@@ -2,8 +2,7 @@ FROM ubuntu:24.04
 COPY ./ /genetIC
 
 RUN apt-get update && DEBIAN_FRONTEND=noninteractive apt-get install -y g++-12 libgsl-dev libfftw3-dev python3-pip pkg-config libhdf5-serial-dev
-RUN apt-get install -y git # temporary for installing pynbody from git, see line below
-RUN pip3 install git+https://github.com/pynbody/pynbody.git --break-system-packages # should use a venv but this is simpler for now
+RUN pip3 install --pre pynbody --break-system-packages # should use a venv but this is simpler for now
 RUN cd /genetIC && make clean && make
 
 ENTRYPOINT ["/genetIC/genetIC"]