Fix sigstore signature file output location

Change to dist/ directory before signing to ensure .sig and .pem files are created in the correct location for the upload step.

Co-authored-by: jacksonpradolima <7774063+jacksonpradolima@users.noreply.github.com>

Author: Copilot

.github/workflows/publish.yml

@@ -41,7 +41,9 @@ jobs:
         run: python -m pip install sigstore==3.5.1
 
       - name: Sign distributions
-        run: sigstore sign dist/*.whl dist/*.tar.gz
+        run: |
+          cd dist
+          sigstore sign *.whl *.tar.gz
 
       - name: Upload release assets
         uses: softprops/action-gh-release@v2