Changed 400 error code to 200 in the template

[VTimofeenko]

If the dynamic validation replies with 400 error code, the following happens:

• Connect UI: validation just fails with a generic error
• CBC Sales wizard logs error 409 in console and continues the purchase process

If the validator replies with status=200 and speciifes the value_error – error is displayed in CBC and Connect as expected

[CLAassistant]

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