Updated tag timestamp

.github/workflows/build-pdf.yml

@@ -26,7 +26,7 @@ jobs:
           # See https://docs.github.com/en/get-started/using-git/dealing-with-special-characters-in-branch-and-tag-names
           git config --global user.name 'GitHub Actions'
           git config --global user.email '[email protected]'
-          TAG=v$(date -u '+%Y-%m-%d_%H-%M-%S_%Z')
+          TAG=v$(date -u '+%Y-%m-%d_%H.%M.%S_%Z')
           echo "$TAG"
           echo "tag=$TAG" >> $GITHUB_OUTPUT
           git tag -a $TAG -m "Published version $TAG" ${GITHUB_SHA}