use igwn epel snapshot

Dockerfile

@@ -24,9 +24,13 @@ RUN dnf -y install https://repo.opensciencegrid.org/osg/3.6/osg-3.6-el8-release-
 RUN dnf -y install \
       bash-completion \
       epel-release \
-      igwn-backports-config && \
+      igwn-backports-config \
+      igwn-epel-config && \
     dnf clean all
 
+# disable upstream epel
+RUN dnf config-manager --set-disabled epel
+
 # enable swig4 module
 RUN dnf -y module enable swig:4.0