update app.co api url
update app.co api url

blockstack/blockstack-portal,blockstack/blockstack-portal,blockstack/blockstack-browser,blockstack/blockstack-browser,blockstack/blockstack-browser,blockstack/blockstack-browser,blockstack/blockstack-browser,blockstack/blockstack-portal,blockstack/blockstack-browser,blockstack/blockstack-portal,blockstack/blockstack-portal