Remove integration tests related to the bundled core CLI
Remove integration tests related to the bundled core CLI

They started to fail and we won't be bundling on the current master
branch anymore, thus we can remove the tests.

There will be a follow-up task about removing the bundling altogether.

dcos/dcos-cli,dcos/dcos-cli,dcos/dcos-cli,dcos/dcos-cli,dcos/dcos-cli