gha: update test-matrix: remove docker 23.x, 26.x, add 25.x

- Mirantis Container Runtime (MCR) 23.0 reached EOL, and the next LTS
  version of MCR is 25.x
- Docker 26.x reached EOL and is no longer maintained

Signed-off-by: Sebastiaan van Stijn <[email protected]>

Author: thaJeztah

.github/workflows/e2e.yml

@@ -39,8 +39,7 @@ jobs:
         engine-version:
           - 28  # latest
           - 27  # latest - 1
-          - 26  # github actions default
-          - 23  # mirantis lts
+          - 25  # mirantis lts
     steps:
       -
         name: Checkout