Fixed N+1 queries issue in /api/v1/consultationbed/

[dhruv-goyal-10]

Proposed Changes

• The related fields of Bed like "bed__facility", "bed__location", "bed__location__facility" were causing the N + 1 queries issue, hence added them in select_related.

• The related fields of prefetched_model asset was also causing the N + 1 queries issue, hence added the related fields of it in select_related, while using Prefetch() object.

• To solve the N + 1 query issue related to is_occupied property of Bed Model, I have made necessary changes in PatientConsultationSerializer, to set the _is_occupied property of Bed instance, whose value is equal to the is_occupied property of Bed Model.

Associated Issue

• Fixes #1339

Merge Checklist

• [ ] Tests added/fixed
• [ ] Update docs in /docs
• [ ] Linting Complete
• [ ] Any other necessary step

Only PR's with test cases included and passing lint and test pipelines will be reviewed

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