The @octokit/plugin- references are not actually (directly) used by
@action/github-script and so only serve to confuse about what exact
version of these is included in the action. The actual versions of
these plugins are set by @action/github.

Ignoring newlines, the dist/index.js file is exactly the same without
listing these dependencies in package.json.

`core.getInput()` always returns a string, so testing for 'not null'
is always true. This then leads to previews set to an array with
a single empty string, breaking accept-header output.

Updated eslint rules should help avoid this issue in future, and new
integration tests verify that the github client configuration now
reflects the intended configuration options.

Without this plugin, the debug setting is, effectively, meaningless as
none of the existing plugins produce log output.

The plugin writes the request options to octokit.log.debug, and response
times as *method path - status in ...ms* to octokit.log.info.