CI: build container image on request only

.forgejo/workflows/build.yaml

@@ -1,21 +1,9 @@
 on:
-  push:
   workflow_dispatch:
-    inputs:
-      verbose:
-        description: "Verbose"
-        required: false
-        default: false
-        type: boolean
 
 jobs:
   build:
     runs-on: container
-    #container:
-    #  image: tiptop:5000/treetrail-backend-ci
-    #  volumes:
-    #    - "uv_cache:/root/.cache/uv"
-    #    - "ca-cert:/etc/containers/certs.d"
     steps:
       - uses: actions/checkout@v4