update default.xml.

default.xml

 <?xml version="1.0" encoding="UTF-8"?>
 <manifest>
   <remote fetch="." name="origin" review="https://openharmony.gitee.com/openharmony/"/>
-  <default remote="origin" revision="OpenHarmony-v2.2-Beta" sync-j="4" clone-depth="1" />
+  <default remote="origin" revision="master" sync-j="4" clone-depth="1" />
   <project name="aafwk_aafwk_lite" path="foundation/aafwk/aafwk_lite"  />
   <project name="ace_engine_lite" path="foundation/ace/ace_engine_lite"  />
   <project name="ai_engine" path="foundation/ai/engine"  />