Replace Buffer.from with new Buffer in tests for backward compatability with older versions of node

Author: rkt2spc

test/schema.alias.test.js

@@ -28,7 +28,7 @@ describe('schema alias option', function() {
       string: 'hello',
       number: 1,
       date: new Date(),
-      buffer: Buffer.from('World'),
+      buffer: new Buffer('World'),
       boolean: false,
       mixed: [1, [], 'three', { four: 5 }],
       objectId: new Schema.Types.ObjectId(),
@@ -73,7 +73,7 @@ describe('schema alias option', function() {
         string: 'hello',
         number: 1,
         date: new Date(),
-        buffer: Buffer.from('World'),
+        buffer: new Buffer('World'),
         boolean: false,
         mixed: [1, [], 'three', { four: 5 }],
         objectId: new Schema.Types.ObjectId(),