test: cover configuration, metadata, and the untested workflow branches

[tas50]

35 examples for a driver with 18 methods, and one of them was testing the wrong thing.

The example that could not fail

context 'when vro_disable_ssl_verify is false' do
  before do
    config[:vro_disable_ssl_verify] = true   # <- true
  end

  it 'returns true' do
    expect(driver.verify_ssl?).to eq(false)  # <- false
  end
end

A copy of the true context with the name changed and nothing else. Both branches of #verify_ssl? were asserting the same thing, so the false path — the one that decides whether the driver validates the vRO server's TLS certificate — had never been executed by a test. Fixed to set false and expect true.

What was untested

area	why it matters
#name	the string kitchen list prints
plugin_version	kitchen diagnose output
configuration defaults	vro_disable_ssl_verify defaulting to false is a security-relevant default and nothing pinned it
required_config	five settings the driver cannot run without, none of them checked
#set_workflow_vars	resets the memoized client, which is the only reason running destroy after create in one process works
#workflow_successful?	neither branch

The #set_workflow_vars test is the one I would keep if I could keep only one: the memoization reset is load bearing and invisible, and a refactor that dropped @vro_client = nil would have gone green.

Verification

• rake test — 51 examples, 0 failures (35 before; 16 new, 1 corrected)
• cookstyle --chefstyle — clean; lib/ is untouched by this PR