Postmark Environment Variables
BOX_PROVIDER_POSTMARK__PROVIDER_FROM
BOX_PROVIDER_POSTMARK__PROVIDER_FROM=<string>
<string> would go into from field. Usually looks like in these: example@example.com, John Doe <noreply@example.com>.
BOX_PROVIDER_POSTMARK__PROVIDER_API__KEY
BOX_PROVIDER_POSTMARK__PROVIDER_PASSWORD=<api_key>
<api_key> is your Postmark API key.