Adjust default bitrate

Author: aboba

samples/encode-decode-worker/index.html

@@ -66,7 +66,7 @@ <h2>WebCodecs in Worker</h2>
 <div id="rateInput">
   <label for="rate">bitrate: </label>
   <input type="text" name="rate" id="rate"
-      value=1000000>
+      value=100000>
 </div>
 
 <div id="keyInput">

samples/encode-decode-worker/js/main.js

@@ -1,7 +1,7 @@
 'use strict';
 
 let preferredResolution;
-let mediaStream, bitrate = 3000000;
+let mediaStream, bitrate = 100000;
 let stopped = false;
 let preferredCodec ="VP8";
 let mode = "L1T3";