[14.0][FIX][product_supplierinfo_intercompany] keep sellers sorted

[Kev-Roche]

_prepare_sellers() method return the records in a specific order. We need to keep this order when returning the records.

[OCA-git-bot]

Hi @sebastienbeau, @kevinkhao, @PierrickBrun, some modules you are maintaining are being modified, check this out!

[github-actions[bot]]

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