Summary:
Changed Danger's config so that it provides advice whenever it finds an issue with the pull request template, instead of posting a warning.
Updated Danger several major versions, from 2 to 7. I worked through any breaking changes, which were minimal (change `yarn danger` to `yarn danger ci`).
Added a flag to have Danger post these messages as GitHub Checks instead of as a comment. This slightly buries Danger's output, as it's no longer posted as a comment, but I believe it integrates more nicely into the GitHub interface.
[GENERAL] [Changed] - GitHub-only change: updated Danger config to be nicer to PRs
Pull Request resolved: https://github.com/facebook/react-native/pull/23334
Differential Revision: D14002313
Pulled By: cpojer
fbshipit-source-id: b97ca7b7bd164646b249b7c64b1134306e0f38a8
