Change oauth redirect to 307

[Ph0tonic]

What this PR does / why we need it:

OAuth2 is broken for non GET requests due to the way browser handle those. The 302 redirection code lead browsers to loose the original method and replacing it with GET.
This PR will allow to fix the first step to make oauth2 work even for non GET requests.

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• CVE Report (Scanner found CVE and adding report)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation only

Which issue/s this PR fixes

Fixes #12636

How Has This Been Tested?

This change has been tested though the officials tests which have been updated.
This change doesn't impact other part of the code, but might be a breaking change for other applications which have hard coded the 302 redirection code. However, change this change will allow to enhance oauth2 protocol to work even for non GET request.

Checklist:

• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I've read the CONTRIBUTION guide
• I have added unit and/or e2e tests to cover my changes.
• All new and existing tests passed.

[linux-foundation-easycla]

The committers listed above are authorized under a signed CLA.

• ✅ login: Ph0tonic / name: Bastien Wermeille (efd71e7)

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This pull-request has been approved by: Ph0tonic
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