feat(authentication-oauth): Allow dynamic oAuth redirect

[daffl]

This pull request allows dynamic oAuth redirects by adding an origins option to the oAuth configuration. This can be added instead of the redirect option to include a list of URLs that are allowed to make oAuth requests. It will use the Referer HTTP header from the original request to redirect back to. For example a configuration like

{
  "authentication": {
    "oauth": {
      "origins": [
        "https://feathersjs.com",
        "https://feathers.cloud"
      ]
    }
  }
}

Would allow and redirect any request made from those domains.

• Closes OAuth2 dynamic redirect doesn't work #2285
• Closes Allow multiple oAuth redirect domains #2430

[emmanuelgeoffray]

Hi @daffl
Thank you for this nice feature.
I think this new origins option should be omitted when authentification-oauth is parsing each strategy.
https://github.com/feathersjs/feathers/blob/dove/packages/authentication-oauth/src/index.ts#L51

[daffl]

@emmanuelgeoffray Can you open a new issue with a more detailed description?