providers/oauth2: fix authentication error with identical app passwords (cherry-pick #17100 to version-2025.8)

[authentik-automation]

Cherry-pick of #17100 to version-2025.8 branch.

Original PR: #17100
Original Author: @BeryJu
Cherry-picked commit: e0f754c

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 92.81%. Comparing base (4403baa) to head (6a35807).
⚠️ Report is 2 commits behind head on version-2025.8.
✅ All tests successful. No failed tests found.

Additional details and impacted files

@@                Coverage Diff                 @@
##           version-2025.8   #17103      +/-   ##
==================================================
+ Coverage           92.65%   92.81%   +0.16%     
==================================================
  Files                 837      837              
  Lines               45349    45362      +13     
==================================================
+ Hits                42018    42104      +86     
+ Misses               3331     3258      -73     

Flag	Coverage Δ
e2e	46.53% <0.00%> (+0.73%)	⬆️
integration	23.53% <0.00%> (-0.01%)	⬇️
unit	90.91% <100.00%> (+0.01%)	⬆️

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[github-actions]

authentik PR Installation instructions

Instructions for docker-compose

Add the following block to your .env file:

AUTHENTIK_IMAGE=ghcr.io/goauthentik/dev-server
AUTHENTIK_TAG=gh-6a35807a9994c05f5207da4607a01feb1ab96873
AUTHENTIK_OUTPOSTS__CONTAINER_IMAGE_BASE=ghcr.io/goauthentik/dev-%(type)s:gh-%(build_hash)s

Afterwards, run the upgrade commands from the latest release notes.

Instructions for Kubernetes

Add the following block to your values.yml file:

authentik:
    outposts:
        container_image_base: ghcr.io/goauthentik/dev-%(type)s:gh-%(build_hash)s
global:
    image:
        repository: ghcr.io/goauthentik/dev-server
        tag: gh-6a35807a9994c05f5207da4607a01feb1ab96873

Afterwards, run the upgrade commands from the latest release notes.