CI: set version from git 4

.forgejo/workflows/build.yaml

@@ -29,12 +29,17 @@ jobs:
 
       - name: Get version with git describe
         id: version
-        run: echo "version=$(git describe)" >> $GITHUB_OUTPUT
+        run: |
+          echo "version=$(git describe)" >> $GITHUB_OUTPUT
+          echo "$VERSION"
 
-      - name: Version
+      - name: Check if the container should be built
+        id: builder
         env:
-          VERSION: ${{ steps.version.outputs.version }}
-        run: echo "$VERSION"
+          RUN: ${{ toJSON(inputs.build || !contains(steps.version.outputs.version, '-')) }}
+        run: |
+          echo "run=$RUN" >> $GITHUB_OUTPUT
+          echo "Run build: $RUN"
 
       - name: Set the version in pyproject.toml (workaround for uv not supporting dynamic version)
         if: fromJSON(steps.builder.outputs.run)