feat: allow postponing applying webpack hot updates

[pieh]

Adding new feature to hot middleware that allow to delay/postpone applying hot updates. This might be needed by gatsbyjs/gatsby#37040 to allow gatsby's resource loader to fetch newly discovered static queries etc before applying code update and hence "syncing" data and code updates together. Without ability to manage when updates are applied, runtime often fails because newly compiled code often relies on static queries that weren't loaded yet and resulting in dreaded "The result of this StaticQuery could not be fetched." errors

[pieh]

we hit node builtin polyfill not set with webpack 5, but URLSearchParams seems to be available in all browsers we support natively.

I also realized there is #2 PR that seems to try to do something about this require as well, so might be good to resolve those 2 together

[LekoArts]

Can be tried with @gatsbyjs/webpack-hot-middleware@alpha-lazy-comp