Make sure Remix SDK works without feature flags

[AbhiPrasad]

https://github.com/remix-run/remix/commits/dev

As brought up in #7810 (comment), future flags are being removed when v2 actually releases. Let's test the SDK against the v2 branch of remix and check if they'll still work.

[huw]

(Just FYI the actual work branch for v2 is dev)

[AbhiPrasad]

Thanks @huw!