feat(auth)!: update default values for env variables

[golobitch]

Changes proposed in this pull request

• Rename two env variables
• Remove default values for some env variables
• Update localenv
• Update integration tests
• Update documentation

Context

fixes #2685

Checklist

• [x] Related issues linked using fixes #number
• [x] Tests added/updated
• [x] Documentation added
• [x] Make sure that all checks pass
• [ ] Bruno collection updated

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[golobitch]

LGTM, there's just the small grammatical note

@njlie can you please check and approve again. I committed your suggestion for that grammatical error.