method ConnectionOptions.pskCallback
Usage in Deno
```typescript import { type ConnectionOptions } from "node:node__tls.d.ts"; ```
ConnectionOptions.pskCallback(hint: string | null): PSKCallbackNegotation | null
When negotiating TLS-PSK (pre-shared keys), this function is called
with optional identity `hint` provided by the server or `null`
in case of TLS 1.3 where `hint` was removed.
It will be necessary to provide a custom `tls.checkServerIdentity()`
for the connection as the default one will try to check hostname/IP
of the server against the certificate but that's not applicable for PSK
because there won't be a certificate present.
More information can be found in the RFC 4279.
PSKCallbackNegotation | null
Return `null` to stop the negotiation process. `psk` must be
compatible with the selected cipher's digest.
`identity` must use UTF-8 encoding.