sync.profile: Point dependencies to 'refs/heads/dev'

We should test dev branches against dev branches only by default.
At some point we should automate the merges from release->stable->dev
and/or decide how to handle possible conflicts.

This is good enough for the time being.

Change-Id: I70b0244db87bd4a7023004bf50629bb790d6dfc2
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

sync.profile

@@ -11,6 +11,6 @@
 #   - any git symbolic ref resolvable from the module's repository (e.g. "refs/heads/master" to track master branch)
 #
 %dependencies = (
-    "qtbase" => "refs/heads/master",
+    "qtbase" => "refs/heads/dev",
 );