publish workflow: Remove unnecessary checkout step (#136)

Author: tangrufus

.github/workflows/publish.yml

@@ -11,7 +11,6 @@ jobs:
     permissions:
       contents: write
     steps:
-      - uses: actions/checkout@v6
       - uses: actions/publish-action@v0.4.0
         with:
           source-tag: ${{ github.ref_name }}