allow disabling the github token

[waldner]

I still maintain that this will potentially break some workflow (after all, the currently published version does use the token for the API requests (https://github.com/bats-core/bats-action/blob/3.0.1/action.yaml#L141), and now it will suddenly stop using it in the new version unless the user takes extra steps, but I think this PR implements the change the way you had suggested.

[brokenpip3]

I still maintain that this will potentially break some workflow (after all, the currently published version does use the token for the API requests (https://github.com/bats-core/bats-action/blob/3.0.1/action.yaml#L141),

before this PR the action was using the github token silently, now we are going to make it optional so the user can choose to pass it or not

and now it will suddenly stop using it in the new version unless the user takes extra steps

it will not stop, just it will make api calls not authenticated and subject to rate limits, but it will not hit the common users unless with an high usage of this action each minutes.
In general passing the token as extra step with with: is a common pattern in the most famous and used actions.
Also don't worry I will cut a major release and write it to the release note :)

but I think this PR implements the change the way you had suggested.

indeed! Thanks for you contribution!