Fix enforce protection logic

[SvanBoxel]

At the moment the app copies all current required status checks as an array and then, depending on whether you enforce it or not, adds a new required check to that array. That means that even though you toggle the boolean from true to false, it will still be part of the original array of required checks.

This PR:

• Removes the context from the required contexts array if it is un-enforced
• Adds specs for the enforce-protections function

Fixes #24

[SvanBoxel]

Release with 1.3.0.