[ci] remove "read all" permission in reusable_release.yml (#11405)

it should be override by  `content: write` anyway

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Author: hannah-hyj

.github/workflows/reusable_release.yml

@@ -8,8 +8,6 @@ on:
       branch-name:
         required: true
         type: string
-# Declare default permissions as read only.
-permissions: read-all
 jobs:
   release:
     if: github.repository_owner == 'flutter'