JCF: Issue #361: hopefully the last act in a comedy of errors where I…

… try to get the cache to be ignored so I can use a different staging location on daq.fnal.gov than normal

.github/workflows/slim_externals.yaml

@@ -42,7 +42,7 @@ jobs:
           echo "FROM ghcr.io/dune-daq/alma9-spack:latest" > Dockerfile
           echo 'MAINTAINER John Freeman "[email protected]"' >> Dockerfile
           echo "ENV REFRESHED_AT $refresh_date" >> Dockerfile
-          echo "RUN pwd"
+          echo "RUN pwd" >> Dockerfile
           echo "ADD spack/externals/ext-v2.1 /cvmfs/dunedaq.opensciencegrid.org/spack/externals/ext-v2.1" >> Dockerfile
           echo "RUN source /cvmfs/dunedaq.opensciencegrid.org/spack/externals/ext-v2.1/spack-0.20.0/share/spack/setup-env.sh && spack uninstall -y llvm" >> Dockerfile
           echo "ADD tools /cvmfs/dunedaq.opensciencegrid.org/tools" >> Dockerfile