A very minimal Resend client for sending emails.
Emails are sent via the [resend_client::ResendClient] which provides both a synchronous and
asynchronous send method. The two are mutually exclusive and accessible via the async feature. The
crate uses reqwest internally.
Currently, this only supports the html Resend parameter as I built this for my own use and
that's all I need. If anyone else is looking into this, however, I would not mind expanding it.