fix(remix-react): avoid duplicate loader calls when using prefetch-intent

[brophdawg11]

This fixes a nuanced issue when using <Link prefetch="intent" /> due to prefetch cache behavior. Subsequent <link rel="prefetch"> elements to the same locations as previous prefetch elements will not leverage prior prefetch cache entries unless the endpoint returned a cache-control header. Couldn't find much official docs on this, but GoogleChromeLabs/quicklink#21 (comment) was the most relevant bit I found.

So, in the scenario described by #1249 when a loader does not return cache-control, the behavior ended up being:

1. Hover on /users/1
   • Adds prefetch links to call the loader for /users/1 which has no cache-control header
2. Navigate to /users/1
   • Standard loader calls use the prefetch cache entry for /users/1
   • Prefetch link elements are removed since it's now an active route
3. Navigate to /users/2
   • Prefetch links were being added back for /users/1 since it was still in a shouldPrefetch state from it's prior hover and is no longer active
   • These subsequent prefetch links would not use the pre-existing prefetch cache and without cache-control would cause another hit to the server for the now inactive route.

This PR updates it such that shouldPrefetch is unset upon navigating to the link in question, thus requiring another hover/focus intent to re-add <link rel="prefetch"> elements. If developers wish to avoid subsequent hits to their loaders on those calls they should leverage a cache-control header which will be respected by the prefetch links.

Closes #1249

• Tests

[brophdawg11]

@ryanflorence Now that we setShouldPrefetch(false) in cancelIntent these tests are invalid since the link tags remove - just confirming that's expected 👍

[github-actions]

🤖 Hello there,

We just published version v0.0.0-nightly-9e5cd6d-20220517 which includes this pull request. If you'd like to take it for a test run please try it out and let us know what you think!

Thanks!

[github-actions]

🤖 Hello there,

We just published version v1.5.0 which includes this pull request. If you'd like to take it for a test run please try it out and let us know what you think!

Thanks!