Remove container specification - use runner's default ubuntu-latest

Match working workflow pattern from other server.
Let runner provide Docker environment directly.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

.gitea/workflows/build-deploy.yml

@@ -8,9 +8,6 @@ on:
 jobs:
   docker:
     runs-on: ubuntu-latest
-    container:
-      image: ghcr.io/catthehacker/ubuntu:full-22.04
-      options: --privileged
 
     steps:
       - name: Checkout code