ci: mark vmware farm as offline
It is currently failing every job with this error:
xmlrpc.client.ProtocolError: <ProtocolError for http://gitlab-runner:ke29n6ld4o3ji2w352lfc61gb1o6o87wuxlo4ljzg5fqogplz3wbu6xl9whzw5fg2lke9ld304ga2c0hubyrnos0e7pp8ooqjgoonyxljp5iq2gac9n0libqdca60j5u@localhost/RPC2: 500 HTTPConnectionPool(host='localhost', port=80): Max retries exceeded with url: /RPC2 (Caused by ResponseError('too many 500 error responses'))>
/cc @blu