Revert "Set default branch for repo"

This is 404ing. It's not strictly needed for the moment, let's
come back to it.

This reverts commit 266b2dd3fc.

Change-Id: Id9ab3c233753025d7a01eb4664ecee6d102bbf19

playbooks/roles/gitea-git-repos/tasks/setup-repo.yaml

@@ -45,17 +45,3 @@
       external_tracker_url: "https://storyboard.openstack.org/#!/project/{{ org }}/{{ repo }}"
       tracker_url_format: https://storyboard.openstack.org/#!/story/{index}
       tracker_issue_style: numeric
-- name: Set default branch
-  uri:
-    url: "{{ gitea_url }}/{{ org }}/{{ repo }}/settings/branches"
-    validate_certs: false
-    user: root
-    password: "{{ gitea_root_password }}"
-    force_basic_auth: true
-    status_code: 302
-    method: POST
-    body_format: form-urlencoded
-    body:
-      _csrf: "{{ gitea_token }}"
-      action: default_branch
-      branch: master