Update scorecard docs to be more clear how to use the configuration file.

What is the URL of the document?

https://sdk.operatorframework.io/docs/advanced-topics/scorecard/scorecard/#configuration

Which section(s) is the issue in?

Configuration

What needs fixing?

A better description of when and how to use the configuration. There are no examples of passing in a configuration on the command line to override the existing config in a bundle. It isn't clear how to add my own tests to this configuration file either.

Additional context

One scenario we'd like is to be able to define tests in a config file and use that file for multiple bundles.

for b in bundles:
    operator-sdk scorecard b --config mytests.yaml