Update TagBot token to use PAT instead of GITHUB_TOKEN

Author: mtfishman

.github/workflows/TagBot.yml

@@ -11,6 +11,6 @@ jobs:
     steps:
       - uses: "JuliaRegistries/TagBot@v1"
         with:
-          token: "${{ secrets.GITHUB_TOKEN }}"
+          token: "${{ secrets.TAGBOT_PAT }}"
           registry: "ITensor/ITensorRegistry"
           ssh: "${{ secrets.DOCUMENTER_KEY }}"