Update GPT based evaluators to force output to be a single integer

[luigiw]

Description

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• The pull request does not introduce [breaking changes].
• CHANGELOG is updated for new features, bug fixes or other significant changes.
• I have read the contribution guidelines.
• I confirm that all new dependencies are compatible with the MIT license.
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• There are a small number of commits, each of which have an informative message. This means that previously merged commits do not appear in the history of the PR. For more information on cleaning up the commits in your PR, see this page.

Testing Guidelines

• Pull request includes test coverage for the included changes.

[github-actions]

promptflow-evals test result

 12 files  ±  0   12 suites  ±0   1h 44m 54s ⏱️ + 34m 15s
 20 tests  -  19   20 ✅  -  18  0 💤  -  1  0 ❌ ±0 
240 runs   - 228  240 ✅  - 216  0 💤  - 12  0 ❌ ±0 

Results for commit 3887aa4. ± Comparison against base commit de5aa0f.

This pull request removes 39 and adds 20 tests. Note that renamed tests count towards both.

tests.evals.e2etests.test_builtin_evaluators.TestBuiltInEvaluators ‑ test_composite_evaluator_chat[False-True]
tests.evals.e2etests.test_builtin_evaluators.TestBuiltInEvaluators ‑ test_composite_evaluator_chat[True-True]
tests.evals.e2etests.test_builtin_evaluators.TestBuiltInEvaluators ‑ test_composite_evaluator_qa[False]
tests.evals.e2etests.test_builtin_evaluators.TestBuiltInEvaluators ‑ test_composite_evaluator_qa[True]
tests.evals.e2etests.test_builtin_evaluators.TestBuiltInEvaluators ‑ test_quality_evaluator_coherence
tests.evals.e2etests.test_builtin_evaluators.TestBuiltInEvaluators ‑ test_quality_evaluator_fluency
tests.evals.e2etests.test_builtin_evaluators.TestBuiltInEvaluators ‑ test_quality_evaluator_groundedness
tests.evals.e2etests.test_builtin_evaluators.TestBuiltInEvaluators ‑ test_quality_evaluator_prompt_based_with_dict_input
tests.evals.e2etests.test_builtin_evaluators.TestBuiltInEvaluators ‑ test_quality_evaluator_relevance
tests.evals.e2etests.test_builtin_evaluators.TestBuiltInEvaluators ‑ test_quality_evaluator_similarity
…

tests.evals.e2etests.test_adv_simulator.TestAdvSimulator ‑ test_adv_conversation_sim_responds_with_responses
tests.evals.e2etests.test_adv_simulator.TestAdvSimulator ‑ test_adv_qa_sim_responds_with_one_response
tests.evals.e2etests.test_adv_simulator.TestAdvSimulator ‑ test_adv_rewrite_sim_responds_with_responses
tests.evals.e2etests.test_adv_simulator.TestAdvSimulator ‑ test_adv_sim_init_with_prod_url
tests.evals.e2etests.test_adv_simulator.TestAdvSimulator ‑ test_adv_summarization_jailbreak_sim_responds_with_responses
tests.evals.e2etests.test_adv_simulator.TestAdvSimulator ‑ test_adv_summarization_sim_responds_with_responses
tests.evals.e2etests.test_adv_simulator.TestAdvSimulator ‑ test_incorrect_scenario_raises_error
tests.evals.e2etests.test_builtin_evaluators.TestBuiltInEvaluators ‑ test_composite_evaluator_content_safety
tests.evals.e2etests.test_builtin_evaluators.TestBuiltInEvaluators ‑ test_composite_evaluator_content_safety_chat[False-False]
tests.evals.e2etests.test_builtin_evaluators.TestBuiltInEvaluators ‑ test_composite_evaluator_content_safety_chat[True-False]
…

♻️ This comment has been updated with latest results.

[w-javed]

LGTM

[luigiw]

Fixes #3522 #3381