tests: Do not use centos-addons or epel repos for the test build

The tmt systems have a number of extra repos installed, and they can
cause package selection conflicts with baseos and appstream. Exclude
them from the list passed to lorax for building the test boot.iso

Related: RHEL-28654

tests/scripts/run_tests.sh

@@ -7,7 +7,8 @@ if [ ! -e /usr/share/lorax/templates.d/80-rhel/ ]; then
 fi
 
 # Gather up the list of system repo files and use them for lorax
-REPOS=$(for f in /etc/yum.repos.d/*repo; do echo -n "--repo $f "; done)
+# Skip centos-addons and all epel repos, these cause conflicts with other release packages
+REPOS=$(find /etc/yum.repos.d/ -maxdepth 1 -type f -name '*\.repo' ! -name 'centos-addons.repo' ! -name 'epel*' -exec echo -n "--repo {} " \;)
 if [ -z "$REPOS" ]; then
     echo "No system repos found"
     exit 1