fix(providers/google): sanitize Dataproc batch labels to use dashes instead of underscores

[YoannAbriel]

Problem

DataprocCreateBatchOperator.__update_batch_labels() replaces dots and spaces with underscores when building GCP labels from DAG/task IDs. GCP labels only allow lowercase letters, numbers, and dashes — underscores are invalid. This causes InvalidArgument errors when task IDs contain underscores (common with task groups, e.g. process_data).

Root Cause

re.sub(r"[.\s]", "_", ...) only strips dots and whitespace, converting them to underscores. Any existing underscores in the ID pass through unchanged. The validation regex r"^[a-z][\w-]{0,62}$" also incorrectly allows underscores via \w.

Additionally, the dag_display_name validation was checking dag_id instead of the actual dag_display_name value.

Fix

• Replace the substitution pattern with re.sub(r"[^a-z0-9-]", "-", ...) — strips everything except valid label characters
• Update the validation regex to r"^[a-z0-9][a-z0-9-]{0,62}$" matching GCP's actual requirements
• Fix the dag_display_name validation to check the right variable
• Added test for underscore/dot sanitization

Closes: #59332

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Was generative AI tooling used to co-author this PR?

• Yes — Claude Code

Generated-by: Claude Code following the guidelines

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