switch to AUTH_SERVICE_JWT_SECRET

[wkloucek]

Description

follow up of owncloud/ocis#7523, to use the right env variable for auth service

Related Issue

• Fixes a part of next branch tracker for oCIS latest 5.0 compatiblity #406
• Follow up of fix auth service env variable ocis#7523

Motivation and Context

How Has This Been Tested?

• run it in minikube

Screenshots (if appropriate):

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Technical debt
• Tests only (no source changes)

Checklist:

• Code changes
• Unit tests added
• Acceptance tests added
• Documentation generated (make docs) and committed
• Documentation ticket raised:
• Documentation PR created:

[wkloucek]

@kobergj could you please give this PR a review in order to keep next some sort of up to date