Backported patches to DD4hep master

Incorporate critical patches to DD4hep (back ported from master):

• https://github.com/AIDASoft/DD4hep/pull/849
• https://github.com/AIDASoft/DD4hep/pull/851

containers/jug/dev.Dockerfile

@@ -80,6 +80,11 @@ RUN echo "repos:" > $SPACK_ROOT/etc/spack/repos.yaml                    \
  && mkdir /opt/spack-environment                                        \
  && mv $SPACK_ROOT/eic-spack/spack.yaml /opt/spack-environment/spack.yaml
 
+## Optional, normally commented out:
+## Nuke the buildcache
+#RUN --mount=type=cache,target=/var/cache/spack-mirror                   \
+#  rm -rf /var/cache/spack-mirror/*
+
 ## This variable will change whenevery either spack.yaml or our spack package
 ## overrides change, triggering a rebuild
 ARG CACHE_BUST="hash"