⚡ Bolt: Optimize HashJoinExec for single build-side batches

[Dandandan]

• 💡 What: Added a fast path to collect_left_input in HashJoinExec to avoid calling concat_batches when the build side consists of a single RecordBatch.
• 🎯 Why: The concat_batches operation is expensive, involving unnecessary memory allocation and data copying. This optimization bypasses this overhead in a common scenario.
• 📊 Impact: Improves hash join performance by reducing memory allocation and CPU usage for single-batch build-side inputs.
• 🔬 Measurement: The performance improvement can be verified by running benchmarks that involve hash joins with single-batch build sides, such as the TPC-H benchmarks.

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PR created automatically by Jules for task 6658239611554231655 started by @Dandandan

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