Chore: Require @packages/example to be reviewed before deployment

[cacieprins]

Current behavior:

@packages/example deploys directly to production example.cypress.io as soon as the deploy command executes, via the gh-pages tool.

As a stopgap to prevent outages:

• gh-pages should be a protected branch
• the deploy command in @packages/example should open a pull request to gh-pages instead of committing directly

In the future:

• cypress-example-kitchensink should deploy continuously to a staging environment
• deploys of cypress-example-kitchensink to example.cypress.io are handled via circleci in the cypress-example-kitchensink repository, triggered by creating a github release as a part of the cypress deploy process
  • this leaves the door open for an automated release triggered by cypress ci, once the cypress release process is automated

[MikeMcC399]

I also discovered that running

yarn workspace @packages/example deploy

from a fork deploys to the fork's gh-pages branch. The web's structure is however not set up to run correctly from a fork, Only the index.html displays correctly. Navigation to other pages does not work and CSS formatting does not work on other pages either.

That may become irrelevant if the deploy process is changed. If not it should be noted in the README.

[MikeMcC399]

Possibly something like Percy could be used for visual comparison of pending changes to https://example.cypress.io ?

[MikeMcC399]

Current drawbacks

• There is no staging step in this process which would allow a pre-deployed example.cypress.io website to be tested before it is moved to production
• There is no testing of backwards compatibility to previous versions of Cypress (see resolved issue https://github.com/cypress-io/cypress-example-kitchensink/issues/819)