fix: process validation report fails when service date fields are empty

[davidgamez]

Summary:

The process validation report fails when an empty string("") is found on the JSON value. This PR ignores the empty string values from the fields; it also adds a helper method to be used in similar situations.

Expected behavior:

The process validation report function should account for missing or empty service date fields

From our AI friend

This pull request includes several changes to add new functionality and improve the codebase for the functions-python project. The most important changes include adding a new helper function get_nested_value, updating the README.md file with instructions for generating HTML coverage reports, and refactoring the generate_report_entities function to use the new helper function.

New functionality:

• functions-python/helpers/transform.py: Added a new helper function get_nested_value to retrieve values from nested dictionaries.
• functions-python/helpers/tests/test_transform.py: Added tests for the new get_nested_value function.

Documentation updates:

• functions-python/README.md: Updated the README file to include instructions for running tests and generating HTML coverage reports.

Code refactoring:

• functions-python/process_validation_report/src/main.py: Refactored the generate_report_entities function to use the new get_nested_value function and moved the service date population logic to a new populate_service_date function. [1] [2]
• functions-python/process_validation_report/tests/test_validation_report.py: Added tests for the new populate_service_date function.

Testing tips:

Teste in DEV, link

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[qcdyx]

LGTM