fix: prevent unwanted evaluation

In older versions of Ansible it attempts to evaluate the nested variable inside `github_kayobe_environment_input` this causes the role to fail if using no environments.

roles/github/defaults/main.yml

@@ -56,13 +56,15 @@ github_kolla_tags_input: |
       The ansible tags to use when running kolla-ansible playbooks.
 
 github_kayobe_environment_input: |
+  {%- if github_environment_selector == 'input' -%}
   kayobe_environment:
     description: |
       Select the environment the kayobe workflow shall target.
     type: choice
     required: true
     default: '{{ github_kayobe_environments | first }}'
     options: {{ github_kayobe_environments }}
+  {%- endif -%}
 
 github_workflows:
   - "{{ github_prepare_runner }}"