style: adding progress bar to llm-based evaluators

[davidsbatista]

Proposed Changes:

This adds an optional progress_bar to the run() method of the base LLMEvaluator class and its dependents. Depending on the dataset, a faithfulness or context relevance evaluation can take several minutes, and the user can opt to be informed of ongoing progress.

[coveralls]

Pull Request Test Coverage Report for Build 9194623363

Warning: This coverage report may be inaccurate.

This pull request's base commit is no longer the HEAD commit of its target branch. This means it includes changes from outside the original pull request, including, potentially, unrelated coverage changes.

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Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.002%) to 90.555%

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Totals
Change from base Build 9176174231:	0.002%
Covered Lines:	6587
Relevant Lines:	7274

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💛 - Coveralls