copr-anubis: allow all non-get requests

Relates: https://github.com/fedora-copr/copr/issues/4110

roles/anubis/templates/policies.yaml.j2.copr-infrastructure

@@ -12,6 +12,14 @@ bots:
     action: ALLOW
     user_agent_regex: packit.dev/packit
 
+  # Non-GET requests bypass Anubis challenge because HTTP redirects turn
+  # them into GET (losing the request body), causing 405 errors.
+  # All non-GET endpoints require login + CSRF token anyway.
+  # https://github.com/fedora-copr/copr/issues/4110
+  - name: allow-non-GET-requests
+    expression: method != "GET"
+    action: ALLOW
+
 {% if copr_machine_type == "frontend" %}
   # Machine/API endpoints - ALLOW without challenge
   # These are used by dnf, copr-cli, webhooks, and internal services