feat(router): add grouping and priority logic in connector utils to handle multiple errors in connector flows (#1765)
Files to modify:


**utils.rs**
  Add:
    - function: private::get_connector_error_type
    - function: pub::get_error_code_error_message_based_on_priority
    - function: private::get_connector_error_type
    - function: private::test_get_error_code_error_message_based_on_priority
    - struct: pub::ErrorCodeAndMessage
    - struct: private::TestConnector
    - enum: pub::ConnectorErrorType
    - trait: pub::ConnectorErrorTypeMapping
    - impl: impl ConnectorErrorTypeMapping for TestConnector
    - mod: private::error_code_error_message_tests