test: Use force flag with lvremove
test: Use force flag with lvremove

On current Ubuntu 18.04, `lvremove` now asks for confirmation:

    Do you really want to remove and DISCARD logical volume TEST1/one? [y/n]: [n]
      Logical volume TEST1/one not removed.

So use the `-f` (force) flag, like the test already does with the other
`lvremove` invocation a few lines below.

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