fix(chip): set input chip leading-space to 12px

[HarmfulBreeze]

According to the design doc, leading padding should be 12dp[1] rather than 16.

Fixes: material-components/material-web#5784

[1] https://m3.material.io/components/chips/specs#1dcff1cb-22f5-41da-809e-6c85b467cff1

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