stop using rt repo for DTK

[Ximinhan]

kernel-rt becomes a sub package since 9.3 in embargoed plashet repo path like https://ocp-artifacts.engineering.redhat.com/pub/RHOCP/plashets/4.17/stream/el9-embargoed/latest/x86_64/os/Packages/kernel-5.14.0-427.50.1.el9_4__x86_64__fd431d51/
in 4.17.8 DTK installed kernel from rhel-9-baseos-rpms and installed kernel-rt from rhel-9-rt-rpms, the kernel-rt from rhel-9-rt-rpms is not the latest

context link https://redhat-internal.slack.com/archives/CB95J6R4N/p1733927479635069

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[openshift-bot]

Validating 1 file(s)...
Validating images/driver-toolkit.yml...
Traceback (most recent call last):
File "/usr/local/bin/validate-ocp-build-data", line 33, in
sys.exit(load_entry_point('rh-ocp-build-data-validator==0.2.5', 'console_scripts', 'validate-ocp-build-data')())
File "/usr/local/lib/python3.9/site-packages/validator/main.py", line 87, in main
validate(f, args.exclude_vpn, args.schema_only)
File "/usr/local/lib/python3.9/site-packages/validator/main.py", line 48, in validate
support.fail_validation(msg, parsed)
File "/usr/local/lib/python3.9/site-packages/validator/support.py", line 14, in fail_validation
raise exceptions.ValidationFailed(msg)
validator.exceptions.ValidationFailed: CGit validation failed for images/driver-toolkit.yml (https://pkgs.devel.redhat.com/cgit/containers/driver-toolkit)
Returned error: This validation must run from a network with access to https://pkgs.devel.redhat.com/cgit