test: fix crypto test case to use correct encoding

The callback would have errored out anyway due to the incorrect
encoding, and that error is not the point of this test case.

PR-URL: https://github.com/nodejs/node/pull/17956
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>

test/parallel/test-crypto-authenticated.js

@@ -389,7 +389,7 @@ for (const test of TEST_CASES) {
       assert.strictEqual(msg, test.plain);
     } else {
       // assert that final throws if input data could not be verified!
-      assert.throws(function() { decrypt.final('ascii'); }, errMessages.auth);
+      assert.throws(function() { decrypt.final('hex'); }, errMessages.auth);
     }
   }