fix: external redirects not being matched correctly closes #3770

[tinfoil-knight]

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Summary

Fixes #3770

External redirects with status code >= 300 & <=400 were not proxied due to requests getting matched incorrectly. This PR fixes the issue by changing the order of matching so that external redirects get matched first.

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[tinfoil-knight]

While working on the issue, I realized that external redirects don't follow the mentioned status code in the _redirects file and all of them have a 200 OK Status. I'm not sure if this is the expected behavior.

To reproduce, just add a redirects file as follows:

/foo https://www.netlify.com/ 299!

[tinfoil-knight]

Note: tests » framework-detection » should start custom command if framework=#custom, command and targetPort are configured is failing on Windows.

Update: Tests aren't failing consistently on all platforms making them hard to debug.

[erezrokah]

This is great @tinfoil-knight 🚀

Sorry for the delay to review, and appreciate the test case!