recipe: allow to disable optionnal apps (#25233)

To disable an app in inventory.yaml, define empty dev-<app>, for
example:

  local:
    hosts:
      localhost:
        tenants_conf:
          dev-fargo:   # disabled
          dev-chrono:  # disabled
          dev-corbo:   # disabled
          dev-bijoe:   # disabled

roles/deploy-tenants/templates/cook-recipe.j2

@@ -33,27 +33,37 @@
         "slug": "eservices",
         "title": "Démarches"
     }},
+    {% if tenants_conf['dev-passerelle'] %}
     {"create-passerelle": {
         "url": "https://{{tenants_conf['dev-passerelle']}}/",
         "template_name": "{{wcs_skeleton_filename}}",
         "title": "Passerelle"
     }},
+    {% endif %}
+    {% if tenants_conf['dev-fargo'] %}
     {"create-fargo": {
         "url": "https://{{tenants_conf['dev-fargo']}}/",
         "title": "Porte-documents"
     }},
+    {% endif %}
+    {% if tenants_conf['dev-chrono'] %}
     {"create-chrono": {
         "url": "https://{{tenants_conf['dev-chrono']}}/",
         "title": "Agendas"
     }},
+    {% endif %}
+    {% if tenants_conf['dev-corbo'] %}
     {"create-corbo": {
         "url": "https://{{tenants_conf['dev-corbo']}}/",
         "title": "Annonces"
     }},
+    {% endif %}
+    {% if tenants_conf['dev-bijoe'] %}
     {"create-bijoe": {
         "url": "https://{{tenants_conf['dev-bijoe']}}/",
         "title": "Statistiques"
     }},
+    {% endif %}
     {"set-theme": {
       "theme": "publik"
     }}