enable tests by default

[garethahealy]

currently, the tests are disabled by default:

• https://github.com/redhat-cop/github-workflows-operators/blob/main/.github/workflows/pr-operator.yml#L20-L34

would it not be better to enable by default and let the consumers of this pipeline be EXPLICIT in disabling tests?

[garethahealy]

thoughts @sabre1041 ?