local-only reporting mode for django_find_annotations

edx-enterprise PR https://github.com/edx/edx-enterprise/pull/424 adds support for PII annotation checking in CI, but since:

1. the django_find_annotations utility always requires annotations for non-local models, and

2. we do not annotate non-local models in repos that do NOT contain an IDA,

...the maximum possible PII annotation coverage for this repo is <100%.

A/C:

• Add a non_local_coverage boolean key to the pii annotation config.

• non_local_coverage: True is the current behavior, and will remain the default.

• non_local_coverage: False will cause non-local models to be ignored, and PII annotation coverage jumps to 100% in edx-enterprise.

• Update edx-enterprise to have 100% coverage after version bump

• Update edx-enterprise to set non_local_coverage = False