[feature] Add `--dev-tools` flag

[developit]

karmatic debug --dev-tools (aliased as --devtools) would use Puppeteer to open DevTools.

To Do

• Can we also have this open the /debug endpoint to enable console access?
• Use this to disable Webpack's optimization.minimize?

[suchipi]

We might actually not need this if we have the --debug flag; in karmatic-nightmare, it just opens DevTools on launch. But with the --debug flag, I think we would need to open dev tools so that people could see the debugger.