Update job permissions (#140476)

Updates to use contents: write and pull-requests: write.

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Author: godofredoc

.github/workflows/minimal.yml

@@ -13,6 +13,9 @@ jobs:
   minimal_token_test:
     name: minimal_token_test
     runs-on: ubuntu-latest
+    permissions:
+      contents: write
+      pull-requests: write
     steps:
       - name: Checkout Flutter Repo
         uses: actions/checkout@b4ffde65f46336ab88eb53be808477a3936bae11