Explain write

Author: hynek

.github/workflows/update-dependencies.yml

@@ -23,7 +23,7 @@ jobs:
       # It doesn't matter if it's deleted when merged, it'll be re-created
       BRANCH_NAME: auto-dependency-upgrades
     permissions:
-      contents: write
+      contents: write  # we need to write to pin files
 
     steps:
       - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2