chore: remove unused linters (#7680)

Remove linters from the repository that are not used. This also removes the Python setup as it was only used for those linters.

Reviewed-on: https://codeberg.org/forgejo/forgejo/pulls/7680
Reviewed-by: Gusted <gusted@noreply.codeberg.org>
Co-authored-by: Lucas Dohmen <lucas@dohmen.io>
Co-committed-by: Lucas Dohmen <lucas@dohmen.io>

.devcontainer/devcontainer.json

@@ -7,10 +7,6 @@
       "version": "22"
     },
     "ghcr.io/devcontainers/features/git-lfs:1.2.3": {},
-    "ghcr.io/devcontainers-contrib/features/poetry:2": {},
-    "ghcr.io/devcontainers/features/python:1": {
-      "version": "3.13"
-    },
     "ghcr.io/warrenbuckley/codespace-features/sqlite:1": {}
   },
   "customizations": {