Having the application request access to the organisation

As an org admin,
I would like label-sync to automatically request access to my organisation
So that it appears in the pending requests section of my 'Third Party Applications' and I can authorise it.

### Further details:

Given all of the changes that Github has been making recently, the default for new repos is now to restrict access to third party applications:

Because of this change, the label-sync app always fails for repos with this restricted access:

The problem isn't so much that access is now required, but that the label-sync application _does not appear in the 'pending requests' section in the org_.

This means that the _only_ way to authorise the application is to temporarily unrestrict third party app access and run label-sync (in which case it works right away). This is not a good way to do it and will severely hamper usage of the application!