Set default revision to android10-release

This wasy it will have the latest source. We don't need to update
the tags all the time except there are projects being added/removed.

Change-Id: Ibf67c2708c2173627ea998dd477d20ac9b560e97

default.xml

@@ -4,7 +4,7 @@
   <remote  name="aosp"
            fetch=".."
            review="https://android-review.googlesource.com/" />
-  <default revision="refs/tags/android-10.0.0_r5"
+  <default revision="android10-release"
            remote="aosp"
            sync-j="4" />