Check that organization allows reviews from third-party tools as early as possible

[augustebaum]

I worked on a PR review, but upon pressing the "submit" button, nothing happens.

The console tells me:

https://api.github.com/repos/<org/project>/pulls/<pull_id>/reviews 403 (Forbidden)

and

Uncaught (in promise) HttpError: Although you appear to have the correct authorization credentials, the 
`<org>` organization has enabled OAuth App access restrictions, meaning that data access to third-parties is 
limited. For more information on these restrictions, including how to enable this app, visit 
https://docs.github.com/articles/restricting-access-to-your-organization-s-data/ 
- https://docs.github.com/rest/pulls/reviews#create-a-review-for-a-pull-request
    at fetchWrapper (chunk-mf7bhnzv.js:22378:11)
    at async chunk-mf7bhnzv.js:22870:16
    at async Object.createPRReview (chunk-mf7bhnzv.js:23407:29)
    at async submitReview (chunk-mf7bhnzv.js:77451:21)
    at async chunk-mf7bhnzv.js:91874:5

So it looks like until I can get those permissions from my org, I cannot use Pulldash for work, and I only learn this at the end of the review process, which means I'll have to rewrite the review.