Update prompt to not include ATTRS part

What does this MR do and why?

Update prompt to not include ATTRS part if doc can't answer the question.

Evaluation results - Collective LLM Judge - Correctness

SHA dda7314d

grade	before_percentage	after_percentage
4	77.8	80
3	22.2	15.0
2	0	5.0
1	0	0

query

WITH grades as (
  SELECT 4 as grade union all
  SELECT 3 as grade union all
  SELECT 2 as grade union all
  SELECT 1 as grade
), before_base_table AS (
  SELECT *
  FROM `dev-ai-research-0e2f8974.duo_chat_experiments.lulalala-464461__collective_llm_judge`
  WHERE answering_model = 'duo-chat'
), after_base_table AS (
  SELECT *
  FROM `dev-ai-research-0e2f8974.duo_chat_experiments.lulalala-464461-1__collective_llm_judge`
  WHERE answering_model = 'duo-chat'
), before_correctness_grade AS (
  SELECT correctness as grade, COUNT(*) as count
  FROM before_base_table
  GROUP BY correctness
), after_correctness_grade AS (
  SELECT correctness as grade, COUNT(*) as count
  FROM after_base_table
  GROUP BY correctness
)

SELECT grades.grade AS grade,
       ROUND((COALESCE(before_correctness_grade.count, 0) / (SELECT COUNT(*) FROM before_base_table)) * 100.0, 1) AS before_percentage,
       ROUND((COALESCE(after_correctness_grade.count, 0) / (SELECT COUNT(*) FROM after_base_table)) * 100.0, 1) AS after_percentage,
FROM grades
LEFT OUTER JOIN before_correctness_grade ON before_correctness_grade.grade = grades.grade
LEFT OUTER JOIN after_correctness_grade ON after_correctness_grade.grade = grades.grade;

Evaluation results - Similarity score

similarity_score_range	before_percentage	after_percentage
1	10	5
0.9	50	60
0.8	30	25
0.7	10	10
0.6	0	0
0.5	0	0
0.4	0	0
0.3	0	0
0.2	0	0
0.1	0	0

query

WITH buckets as (
  SELECT 1.0 as bucket union all
  SELECT 0.9 as bucket union all
  SELECT 0.8 as bucket union all
  SELECT 0.7 as bucket union all
  SELECT 0.6 as bucket union all
  SELECT 0.5 as bucket union all
  SELECT 0.4 as bucket union all
  SELECT 0.3 as bucket union all
  SELECT 0.2 as bucket union all
  SELECT 0.1 as bucket
), before_similarity_score AS (
  SELECT *
  FROM `dev-ai-research-0e2f8974.duo_chat_experiments.lulalala-464461__similarity_score`
  WHERE answering_model = 'duo-chat'
), after_similarity_score AS (
  SELECT *
  FROM `dev-ai-research-0e2f8974.duo_chat_experiments.lulalala-464461-1__similarity_score`
  WHERE answering_model = 'duo-chat'
)

SELECT buckets.bucket AS similarity_score_range,
    (
        SELECT ROUND((COUNT(*) / (SELECT COUNT(*) FROM before_similarity_score)) * 100.0, 1)
        FROM before_similarity_score
        WHERE buckets.bucket = ROUND(before_similarity_score.comparison_similarity, 1)
    ) AS before_percentage,
    (
        SELECT ROUND((COUNT(*) / (SELECT COUNT(*) FROM after_similarity_score)) * 100.0, 1)
        FROM after_similarity_score
        WHERE buckets.bucket = ROUND(after_similarity_score.comparison_similarity, 1)
    ) AS after_percentage,
FROM buckets

MR acceptance checklist

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Related to #464461