fix: add epel-release dep

[kratsg]

Trying to solve the following

#10 64.24 + dnf install -y [https://linuxsoft.cern.ch/wlcg/el9/x86\_64/wlcg-repo-1.0.0-1.el9.noarch.rpm](https://linuxsoft.cern.ch/wlcg/el9/x86_64/wlcg-repo-1.0.0-1.el9.noarch.rpm)
#10 64.46 Last metadata expiration check: 0:00:03 ago on Wed Feb 25 08:34:13 2026.
#10 65.23 wlcg-repo-1.0.0-1.el9.noarch.rpm 12 kB/s | 8.1 kB 00:00
#10 65.28 Dependencies resolved.
#10 65.28 ================================================================================
#10 65.28 Package Architecture Version Repository Size
#10 65.28 ================================================================================
#10 65.28 Installing:
#10 65.28 wlcg-repo noarch 1.0.0-1.el9 @commandline 8.1 k
#10 65.28
#10 65.28 Transaction Summary
#10 65.28 ================================================================================
#10 65.28 Install 1 Package
#10 65.28
#10 65.28 Total size: 8.1 k
#10 65.28 Installed size: 1.9 k
#10 65.28 Downloading Packages:
#10 65.28 Running transaction check
#10 65.28 Transaction check succeeded.
#10 65.28 Running transaction test
#10 65.28 Transaction test succeeded.
#10 65.28 Running transaction
#10 65.29 Preparing : 1/1
#10 65.30 Installing : wlcg-repo-1.0.0-1.el9.noarch 1/1
#10 65.33 Verifying : wlcg-repo-1.0.0-1.el9.noarch 1/1
#10 65.35
#10 65.35 Installed:
#10 65.35 wlcg-repo-1.0.0-1.el9.noarch
#10 65.35
#10 65.35 Complete!
#10 65.37 + dnf install -y HEP\_OSlibs
#10 66.94 WLCG Repository 143 kB/s | 200 kB 00:01
#10 67.50 Error:
#10 67.50 Problem: cannot install the best candidate for the job
#10 67.50 - nothing provides nvtop(x86-64) needed by HEP\_OSlibs-9.2.6-3.el9.x86\_64 from wlcg
#10 67.50 - nothing provides ccache(x86-64) needed by HEP\_OSlibs-9.2.6-3.el9.x86\_64 from wlcg
#10 67.50 (try to add '--skip-broken' to skip uninstallable packages or '--nobest' to use not only best candidate packages)