Add gNMI OpenConfig collector tests and utility functions

- Introduced new test suite for gNMI OpenConfig collector with comprehensive test cases for GET methods.
- Implemented utility functions for managing configurations and checking updates.
- Created storage and tools modules to support test data management and resource composition.
- Removed obsolete test files and JSON topology data to streamline the test structure.
- Added logging for better traceability during test execution.
- Added extra time for context and NBI service to get deployed.