feat: allow to specify a different repository to deploy to

[MH4GF]

Resolves #41

Description

Thank you for creating this fantastic action!
I've added a feature to deploy previews to GitHub Pages of another repository. The following inputs have been added:

• deploy-repository ... Specify the repository name to deploy. This is an input that can be passed to JamesIves/github-pages-deploy-action. The default is github.repository.
• token ... The default GITHUB_TOKEN does not have enough permissions since it will be pushing to another repository. Therefore, the ability to pass a token is added.

These inputs are passed to JamesIves/github-pages-deploy-action.

Also, the pagesurl can be changed to the repository to deploy to.

Motivation

On the site I manage, I deploy to GitHub Pages using the beta version of GitHub Actions.
As a result, I'm facing the same problem as in this issue: #21, and I would like to deploy the preview environment to another repository as a workaround.

Verification

I have prepared the following two repositories and verified the operation:

• source repo ... https://github.com/MH4GF/test-pr-preview-source
  • workflows ... https://github.com/MH4GF/test-pr-preview-source/actions/workflows/deploy-preview.yml
• target repo ... https://github.com/MH4GF/test-pr-review-target
• preview(target repo) ... https://mh4gf.github.io/test-pr-review-target/pr-preview/pr-3/
• preview(source repo, check regression) ... https://mh4gf.github.io/test-pr-preview-source/pr-preview/pr-3/

[rossjrw]

Looks good to me! I've made some documentation changes. Thanks for the contribution @MH4GF!

[rossjrw]

Released in v1.4.0 (https://github.com/rossjrw/pr-preview-action/releases/tag/v1.4.0)