ci: use custom build image

.github/workflows/schema.yml

@@ -13,6 +13,7 @@ jobs:
   publish-schema:
     name: 'Publish Schema'
     runs-on: ubuntu-latest
+    container: ghcr.io/jakestanger/ironbar-build:master
 
     steps:
       - uses: actions/checkout@v3
@@ -20,9 +21,6 @@ jobs:
       - uses: Swatinem/rust-cache@v2
         name: Cache dependencies
 
-      - name: Install build deps
-        run: ./.github/scripts/ubuntu_setup.sh
-
       - name: Build
         run: cargo build --features schema