WebCrypto: fixed RSA JWK test data for Node.js compatibility.

WebCrypto: fixed RSA JWK test data for Node.js compatibility.

Removed the incorrect "alg":"RS256" field from RSA JWK test data
files.  The field is optional per RFC 7517, and the value RS256
(RSASSA-PKCS1-v1_5) was wrong for tests that use RSA-OAEP and
RSA-PSS algorithms.  Node.js correctly rejects JWK imports when
the "alg" field does not match the requested algorithm.

The hash mismatch negative test was updated to use an inline JWK
with an explicit "alg" field instead of the shared file.

This ensures: `test/test262 --binary=node test/webcrypto` pass.