doc: remove typo in crypto.md

Change "its[sic] recommended to" to "be sure to". This fixes a typo and
also improves the passive and indirect phrasing to a more concise active
and direct phrasing.

PR-URL: #34698
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Richard Lau <riclau@uk.ibm.com>
Reviewed-By: Anto Aravinth <anto.aravinth.cse@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>

doc/api/crypto.md

@@ -868,7 +868,7 @@ If `outputEncoding` is given a string will be returned; otherwise a
 `ERR_CRYPTO_ECDH_INVALID_PUBLIC_KEY` error when `otherPublicKey`
 lies outside of the elliptic curve. Since `otherPublicKey` is
 usually supplied from a remote user over an insecure network,
-its recommended for developers to handle this exception accordingly.
+be sure to handle this exception accordingly.
 
 ### `ecdh.generateKeys([encoding[, format]])`
 <!-- YAML