EREGCSC-2901 Fix for "Subject counts include unapproved items"

[cgodwin1]

Resolves #2901

Note:

Failing CDK deployments are not relevant to this bugfix, please ignore them as long as other tests and deployment steps are passing.

Description-

Bug discovered in /v3/resources/subjects where the public_resources and internal_resources fields included unapproved resources in their counts.

This pull request changes...

• Added an approved filter to the existing counts
• Added a test case for this endpoint

Steps to manually verify this change...

1. Unit tests pass
2. Go to the experimental subjects endpoint and note in the first result, "Aged, Blind, Disabled", the public_resources count is 42.
3. Go to this resource in the admin panel and uncheck "Approved" and save.
4. Go back to the subjects endpoint page above and refresh. The public_resources count under "Aged, Blind, Disabled" should drop to 41.

[github-actions]

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[PhilR8]

LGTM!