Honour hash algo and set salt length when generating RSA-PSS key pairs

[gnarea]

As shown in the snipped below, this library isn't currently honouring the hashing algorithm or setting a salt length when generating RSA-PSS keys, as it wasn't supported in older versions of Node.js:

webcrypto/src/mechs/rsa/crypto.ts

Lines 37 to 48 in 37dff39

	const keys = crypto.generateKeyPairSync("rsa", {
	modulusLength: algorithm.modulusLength,
	publicExponent,
	publicKeyEncoding: {
	format: "der",
	type: "spki",
	},
	privateKeyEncoding: {
	format: "der",
	type: "pkcs8",
	},
	});

I think this crypto.generateKeyPairSync() call should be changed to set the type to rsa-pss (only if using RSA-PSS) and add the following options if the current Node.js version is >= 16.10.0:

• hashAlgorithm and mgf1HashAlgorithm: This value is already available in the context (algorithm.hash.name).
• saltLength: Should match the length of the digest from hashAlgorithm (e.g., 32 for SHA-256), following industry best practices (see, for example, TLS 1.3 and GCP KMS key algorithms).

I suspect this might be a breaking change in those apps/libs using the default values of MGF1 with SHA-1 and saltLength=20 (I think PKI.js' SignedData and Certificate might be affected from a cursory look at CryptoEngine but haven't had the time to double check).