Nightlies fail if there were no changes

[snowystinger]

🐛 Bug Report

Nightly builds of RSP will fail (sending a failure e-mail) if there were no changes since the last nightly. It'd be better if we just didn't run that workflow if there were no changes.

🤔 Expected Behavior

😯 Current Behavior

💁 Possible Solution

🔦 Context

💻 Code Sample

🌍 Your Environment

Software	Version(s)
react-spectrum
Browser
Operating System

🧢 Your Company/Team

🕷 Tracking Issue (optional)

[dannify]

Used to it now. One day we will revisit this.