fix: redirect with real scheme from X-Forwarded-Proto

[segaq44]

Proposed changes

Redirections are now based on X-Forwarded-Proto when it exists.
This fixes integrations issues behind load balancers or proxy. The browser was redirected with a wrong protocol.
Issue #433

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[github-actions]

✅ All required contributors have signed the F5 CLA for this PR. Thank you!
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[dekobon]

Thank you for the contribution. Unfortunately, I'll need you to make the CLA bot happy before we can merge.

[segaq44]

I have hereby read the F5 CLA and agree to its terms