bump the sigstore action since v.1.2.3 is crashing

Author: fra-pcmgf

.github/workflows/publish-release.yml

@@ -76,7 +76,7 @@ jobs:
         name: python-package-distributions
         path: dist/
     - name: Sign the dists with Sigstore
-      uses: sigstore/gh-action-sigstore-python@v1.2.3
+      uses: sigstore/gh-action-sigstore-python@v2.1.1
       with:
         inputs: >-
           ./dist/*.tar.gz