Add test coverage to makefile (#367)

**Related Issue(s):**

- #87 

**Description:**
- Added code coverage reporting to the test suite using pytest-cov.

**PR Checklist:**

- [x] Code is formatted and linted (run `pre-commit run --all-files`)
- [x] Tests pass (run `make test`)
- [x] Documentation has been updated to reflect changes, if applicable
- [x] Changes are added to the changelog

Author: jonhealy1

CHANGELOG.md

@@ -9,9 +9,11 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 
 ### Added
 
+- Added code coverage reporting to the test suite using pytest-cov. [#87](https://github.com/stac-utils/stac-fastapi-elasticsearch-opensearch/issues/87)
+
 ### Changed
 
-- Updated dynamic mapping for items to map long values to double versus float [#326](https://github.com/stac-utils/stac-fastapi-elasticsearch-opensearch/pull/326)
+- Updated dynamic mapping for items to map long values to double versus float. [#326](https://github.com/stac-utils/stac-fastapi-elasticsearch-opensearch/pull/326)
 - Extended Datetime Search to search on start_datetime and end_datetime as well as datetime fields. [#182](https://github.com/stac-utils/stac-fastapi-elasticsearch/pull/182)
 - Changed item update operation to use Elasticsearch index API instead of delete and create for better efficiency and atomicity. [#75](https://github.com/stac-utils/stac-fastapi-elasticsearch-opensearch/issues/75)
 

Makefile

@@ -75,10 +75,10 @@ test-opensearch:
 
 .PHONY: test
 test:
-	-$(run_es) /bin/bash -c 'export && ./scripts/wait-for-it-es.sh elasticsearch:9200 && cd stac_fastapi/tests/ && pytest'
+	-$(run_es) /bin/bash -c 'export && ./scripts/wait-for-it-es.sh elasticsearch:9200 && cd stac_fastapi/tests/ && pytest --cov=stac_fastapi --cov-report=term-missing'
 	docker compose down
 
-	-$(run_os) /bin/bash -c 'export && ./scripts/wait-for-it-es.sh opensearch:9202 && cd stac_fastapi/tests/ && pytest'
+	-$(run_os) /bin/bash -c 'export && ./scripts/wait-for-it-es.sh opensearch:9202 && cd stac_fastapi/tests/ && pytest --cov=stac_fastapi --cov-report=term-missing'
 	docker compose down
 
 .PHONY: run-database-es