bots: Drop redundant cockpit-system install on openshift
bots: Drop redundant cockpit-system install on openshift

This happens after `dnf clean all` and zerodisk, so just unnecessarily
adds back the yum package index.

martinpitt/cockpit,moraleslazaro/cockpit,mareklibra/cockpit,cockpit-project/cockpit,SotolitoLabs/cockpit,mareklibra/cockpit,cockpituous/cockpit,deryni/cockpit,garrett/cockpit,andreasn/cockpit,cockpituous/cockpit,deryni/cockpit,moraleslazaro/cockpit,andreasn/cockpit,martinpitt/cockpit,cockpituous/cockpit,stefwalter/cockpit,cockpituous/cockpit,moraleslazaro/cockpit,mareklibra/cockpit,martinpitt/cockpit,SotolitoLabs/cockpit,stefwalter/cockpit,mvollmer/cockpit,SotolitoLabs/cockpit,moraleslazaro/cockpit,deryni/cockpit,SotolitoLabs/cockpit,moraleslazaro/cockpit,cockpit-project/cockpit,cockpit-project/cockpit,mvollmer/cockpit,mvollmer/cockpit,mareklibra/cockpit,cockpituous/cockpit,stefwalter/cockpit,mareklibra/cockpit,SotolitoLabs/cockpit,andreasn/cockpit,garrett/cockpit,cockpit-project/cockpit,stefwalter/cockpit,moraleslazaro/cockpit,mareklibra/cockpit,andreasn/cockpit,cockpit-project/cockpit,stefwalter/cockpit,SotolitoLabs/cockpit,stefwalter/cockpit,cockpituous/cockpit,mareklibra/cockpit,moraleslazaro/cockpit,SotolitoLabs/cockpit,andreasn/cockpit,deryni/cockpit,deryni/cockpit,stefwalter/cockpit,garrett/cockpit,andreasn/cockpit,deryni/cockpit,deryni/cockpit,andreasn/cockpit,mvollmer/cockpit,martinpitt/cockpit,martinpitt/cockpit,mvollmer/cockpit,garrett/cockpit,garrett/cockpit