Revise lessons to teach async/await

[hfaerber]

Network Request Lesson:
http://127.0.0.1:4000/module3/lessons/network_requests

React Advanced Data Management Lesson
http://127.0.0.1:4000/module3/lessons/react_advanced_data_management

Update the two lessons above to present async/await with try/catch to mirror the current documentation rather than .then

[hfaerber]

We'd collectively decided to go straight into teaching them async/await and try/catch to mirror the current documentation. I don't think this change should be prioritized right now but I do think we need to make this change when the curriculum updates are finished. This ticket is low priority until other curriculum updates are done.