refactor: update to use a pydantic field to be safer

[MichaelLi65535]

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[codspeed-hq]

CodSpeed WallTime Performance Report

Merging #31942 will not alter performance

_{Comparing MichaelLi65535:retrievers/update-field-pydantic (7e39801) with master (a041314)}

⚠️ Unknown Walltime execution environment detected

Using the Walltime instrument on standard Hosted Runners will lead to inconsistent data.

For the most accurate results, we recommend using CodSpeed Macro Runners: bare-metal machines fine-tuned for performance measurement consistency.

Summary

✅ 13 untouched benchmarks

[codspeed-hq]

CodSpeed Instrumentation Performance Report

Merging #31942 will not alter performance

_{Comparing MichaelLi65535:retrievers/update-field-pydantic (7e39801) with master (a041314)}

Summary

✅ 14 untouched benchmarks

[mdrxy]

Instead of Field we should be using field

[mdrxy]

@MichaelLi65535