fix: correct log placeholder kwarg for untriggered pipeline breakpoint warning

[Kropiunig]

The warning that fires when a pipeline breakpoint is never triggered used the placeholder {break_point} in its message, but passed the value under the kwarg pipeline_breakpoint. Haystack's logger catches the resulting KeyError from msg.format(**safe_extra) and falls back to the raw string, so users saw the literal text {break_point} instead of the actual breakpoint.

Renaming the kwarg to break_point so it matches the placeholder makes the message interpolate the real value. One-line change; the message string is unchanged.

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1 Skipped Deployment

Project	Deployment	Actions	Updated (UTC)
haystack-docs	Ignored	Preview	Jul 6, 2026 1:16pm

[davidsbatista]

Hi @Kropiunig - can you please sign the CLA?

[github-actions]

Coverage report

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File	Statements	Missing	Coverage	Coverage (new stmts)	Lines missing
haystack/core/pipeline
async_pipeline.py
pipeline.py
Project Total

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