Remove the my_application resource from the resin model

[thgreasi]

Users should be using user__has_direct_access_to__application instead.

Resolves: #1096 Change-type: patch See: https://balena.fibery.io/Work/Project/Server-side-pagination-for-devices-Cycle-3-539

[joshbwlng]

@thgreasi A couple quick questions:

• Since we're removing something from the model, is this not considered a breaking change?
• I don't see how this PR relates to the linked Fibery document, is there a TLDR somewhere?

[thgreasi]

@joshbwlng since we are only removing it from the unstable resin model, this is not considered a major, since nobody should be using that (and in oB we also do not expose it at all by default). The linked Fibery project is about releasing the v7 model, but then I realized that there is a number of "breaking changes" that we want to do with v7, and this is one of them. More context: The my_application is already not available on bC's /resin, and was replaced by the user-has direct access to-application computed term some years back. I'm not sure how we missed it in oB :-/