Stripe: can't set tax_rate or dynamic_tax_rate in lineItem

Expected behaviour:
When adding the parameter dynamic_tax_rate or tax_rate to the lineItems array, I expect the ‘create session’ post request to stripe to contain these parameters.

Reproduce:

1. Set a lineItems array, like so:
   {{[{price: "price_EXISTINGID", quantity: 1, tax_rates: ["txr_EXISTING_TAX_ID"]}]}}

   

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2. Use that array in the ‘Create Checkout Session’ like so:

   

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3. Open server action in browser with outputs on to double check that the lineItems are set properly

   

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   you can see the tax_rates being set

4. Start the checkout on the page, which loads successfully. Then go to the logs in stripe. There you see it’s missing in the Request POST body

   

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