Fix version extraction command in workflow

Author: successbyfailure

.github/workflows/docker.yml

@@ -18,12 +18,7 @@ jobs:
       - name: Extract version
         id: version
         run: |
-          VERSION=$(python - <<'PY'
-            import tomllib
-            data = tomllib.load(open("pyproject.toml", "rb"))
-            print(data["project"]["version"])
-          PY
-          )
+          VERSION=$(python -c "import tomllib; print(tomllib.load(open('pyproject.toml','rb'))['project']['version'])")
           echo "version=${VERSION}" >> $GITHUB_OUTPUT
 
       - name: Set up QEMU