fix(FEC-13878): enable hls worker (#218)

### Description of the Changes

**the issue:**
hls worker is not working.

**solution:**
remove configuration that disabled the worker.

**related PR:** kaltura/kaltura-player-js#776

#### Resolves FEC-13878

src/default-config.json

@@ -7,8 +7,7 @@
   },
   "hlsConfig": {
     "fragLoadingMaxRetry": 4,
-    "maxMaxBufferLength": 60,
-    "enableWorker": false
+    "maxMaxBufferLength": 60
   },
   "network": {}
 }