Update TagBot.yml (#7)

Tag was not generated.
So, I figured out this line would be needed.

Author: kdw503

.github/workflows/TagBot.yml

@@ -29,3 +29,4 @@ jobs:
         with:
           token: ${{ secrets.GITHUB_TOKEN }}
           ssh: ${{ secrets.DOCUMENTER_KEY }}
+          registry: HolyLab/HolyLabRegistry