'algorithm_request' test helper method refactored.

Created by: ThanKarab

Changelog:

• Removed leftover code from previous implementations.
• Refactored all the expected test cases, changing filters to null.
• An algorithm_name is defined at the beginning.
• The expected test cases file is loaded based on the algorithm_name.
• Removed 'expected_file' from algo tests, added it inside get_test_params.