Bugfix 404 response from getFlowError

[eh-steve]

Since kratos has only implemented the /self-service/errors?id=some_error_id endpoint for id=stub:500, the current behaviour of the errors page is to always redirect to a 404 error instead of showing the original error.

This PR makes it preserve the original error if kratos returns a 404

Checklist

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• I have referenced an issue containing the design document if my change introduces a new feature.
• I have read the security policy.
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• I have added tests that prove my fix is effective or that my feature works.
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1 out of 2 committers have signed the CLA.

✅ eh-steve
❌ Anonymous

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[aeneasr]

Thank you for your contribution! We are moving to a new version of Ory Elements, where this is no longer a problem. Thus, I'm closing PRs against the old elements, which you can now find here: https://github.com/ory/elements-legacy