test: fix selenium test MachinesStoragePoolTestSuite.testCheckStoragePool
test: fix selenium test MachinesStoragePoolTestSuite.testCheckStoragePool

Commit e25b0d adjusted the breadcrumbs but didn't adjust the
testCheckStoragePool which started failing.

Closes #12997
cockpituous/cockpit,martinpitt/cockpit,moraleslazaro/cockpit,martinpitt/cockpit,garrett/cockpit,martinpitt/cockpit,mvollmer/cockpit,mvollmer/cockpit,garrett/cockpit,cockpituous/cockpit,deryni/cockpit,deryni/cockpit,cockpit-project/cockpit,garrett/cockpit,moraleslazaro/cockpit,deryni/cockpit,cockpituous/cockpit,moraleslazaro/cockpit,cockpit-project/cockpit,cockpit-project/cockpit,cockpit-project/cockpit,moraleslazaro/cockpit,cockpituous/cockpit,mvollmer/cockpit,moraleslazaro/cockpit,deryni/cockpit,cockpit-project/cockpit,cockpituous/cockpit,garrett/cockpit,moraleslazaro/cockpit,mvollmer/cockpit,deryni/cockpit,martinpitt/cockpit,garrett/cockpit,cockpituous/cockpit,martinpitt/cockpit,deryni/cockpit,deryni/cockpit,mvollmer/cockpit,moraleslazaro/cockpit