Updates a ChannelPartnerRepricingConfig. Call this method to set modifications for a specific ChannelPartner's bill. This method overwrites the existing CustomerRepricingConfig. You can only update configs if the RepricingConfig.effective_invoice_month is a future month. To make changes to configs for the current month, use CreateChannelPartnerRepricingConfig, taking note of its restrictions. You cannot update the RepricingConfig.effective_invoice_month. When updating a config in the future: * This config must already exist. Possible Error Codes: * PERMISSION_DENIED: If the account making the request and the account being queried are different. * INVALID_ARGUMENT: Missing or invalid required parameters in the request. Also displays if the updated config is for the current month or past months. * NOT_FOUND: The ChannelPartnerRepricingConfig specified does not exist or is not associated with the given account. * INTERNAL: Any non-user error related to technical issues in the backend. In this case, contact Cloud Channel support. Return Value: If successful, the updated ChannelPartnerRepricingConfig resource, otherwise returns an error.