Unexpected file tmp.yaml in microprofile-reactive-messaging-kafka quickstart

There is a unexpected file named `tmp.yaml` in microprofile-reactive-messaging-kafka quickstart.

It is not mentioned anywhere in the README so it seems unused, probably a leftover from developing the quickstart.

We shouldn't include such things in our published bits.

If for some reason the file is relevant, it should definitely be named differently and its purpose should be obvious (eg. mentioned in README)