Issue Summary

Exempt source branches don't apply when there are 2 required builds with the same destination branch

Steps to Reproduce

1. Create a required build with `release` branch model set as the destination and add an exempt source branch e.g. `first/**`
2. Create another required build with `release` branch model set as the destination and add a different exempt source branch e.g. `second/**`
3. Create a branch with the `second/` prefix and then raise a pull request

Expected Results

There will be no merge checks involving a required build

Actual Results

There is a merge check with the required build

Workaround

Only the first required build exemption seems to apply. Only have 1 exempt source branch for every unique destination branch