Add a command to reset the provider-settings.yaml back to extension shipped default

[sjd78]

Add a new command that will:

1. Config the action
2. Move an existing provider-settings.yaml to provider-settings-${YYYYMMDD}.yaml
3. Copy the extension's sample-provider-settings.yaml in place

This could be useful if and when the sample file gets more/better examples or comments

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FWIW, the sample file is only pushed to the actual provider-settings.yaml when the latter doesn't exist. Maybe a command to "reset provider settings to extension defaults" would be useful? That command should not just overwrite, but move the existing file to ${basename}.YYYYMMDD.yaml kind of thing...

Originally posted by @sjd78 in #261 (review)