Disable syncbase-mojo and reader presubmit tests until syncbase API change is done.
Disable syncbase-mojo and reader presubmit tests until syncbase API change is done.

Change-Id: Ica4cdc9a6733749e3e1e8dcb11d8da8ee17a6dee

vanadium/go.devtools,vanadium/go.devtools,vanadium/go.devtools