implement confidence=True for relation_extraction

[rafmacalaba]

include_confidence=True not working on relation_extraction.

results = extractor.extract_relations(
     "John works for Apple Inc. Mary works for Google.",
     ["works_for"],
    format_results=True,
    include_confidence=True
)
output is
{'relation_extraction': {'works_for': [('John', 'Apple Inc.'),
   ('Mary', 'Google')]}}

After the implementation
Desired Output

{'relation_extraction': {'works_for': [(('John', 0.999244213104248, 0, 1), ('Apple Inc.', 0.9919405579566956, 3, 6)), (('Mary', 0.9999995231628418, 6, 7), ('Google', 0.9999977350234985, 9, 10))]}}

it is also adhering to the format of the entities so this update is much more necessary.

[rafmacalaba]

@urchade for your review!