buffer: allow invalid encoding in from

Looks like a bug to me but the change should probably
done in a semver majpr.

PR-URL: #54533
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Benjamin Gruenbaum <benjamingr@gmail.com>
Reviewed-By: Jake Yuesong Li <jake.yuesong@gmail.com>
Reviewed-By: Rafael Gonzaga <rafael.nunu@hotmail.com>

lib/buffer.js

@@ -476,7 +476,7 @@ function createFromString(string, ops, length = ops.byteLength(string)) {
 
 function fromString(string, encoding) {
   let ops;
-  if (!encoding || encoding === 'utf8') {
+  if (!encoding || encoding === 'utf8' || typeof encoding !== 'string') {
     ops = encodingOps.utf8;
   } else {
     ops = getEncodingOps(encoding);

test/parallel/test-buffer-from.js

@@ -139,3 +139,6 @@ throws(() => {
     code: 'ERR_OUT_OF_RANGE',
   })
 );
+
+// Invalid encoding is allowed
+Buffer.from('asd', 1);