[SwiftUI] Adds forcesEarlySwiftUIRendering flag to fix SwiftUI Cell Sizing

[brynbodayle]

Change summary

• an updated version of this PR using a collection view configuration flag [SwiftUI] Fix reused UIHostingController sizing #152

How was it tested?

How did you verify that this change accomplished what you expected? Add more detail as needed.

• Wrote automated tests
• Built and ran on the iOS simulator
• Built and ran on a device

Pull request checklist

All items in this checklist must be completed before a pull request will be reviewed.

• Risky changes have been put behind a feature flag, e.g. CollectionViewConfiguration
• Added a CHANGELOG.md entry in the "Unreleased" section for any library changes

[brynbodayle]

Necessary to cast to this since EpoxySwiftUIHostingView uses generics

[MichaelGofron]

@brynbodayle did you check in app that we're sending the right image size with these changes? I'd recalled having some issues with the render being called before the boolean flag was set when I was passing through the collection view configuration so just want to make sure we've tested the carousel case.