Restore sequential migration script

[lkostrowski]

Despite being faster, some of the migration calls were rejected due to underlying Saleor mechanisms

This PR restores "slow" migration but it will be rate-limited again, hopefully making it reliable

In the future we can control this via env:

• in production make it slow but reliable
• in dev/staging make it fast, but accept the failure

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Latest commit: 2bb83f6669c05c7a6b9c6fab8a52aec78d23adea

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Name	Status	Preview	Comments	Updated (UTC)
saleor-app-avatax	✅ Ready (Inspect)	Visit Preview	💬 Add feedback	Sep 12, 2024 8:43am

6 Skipped Deployments

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