Fix GH action permissions in rust.yml and docs.yaml workflows (#21884)

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Followup to #21838 for the rest
of the workflows

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Author: Jefffrey

.github/workflows/docs.yaml

@@ -27,6 +27,8 @@ on:
 name: Deploy DataFusion site
 
 jobs:
+  permissions:
+    contents: write
   build-docs:
     name: Build docs
     runs-on: ubuntu-latest

.github/workflows/rust.yml

@@ -42,6 +42,9 @@ on:
   # https://docs.github.com/en/actions/managing-workflow-runs/manually-running-a-workflow
   workflow_dispatch:
 
+permissions:
+  contents: read
+
 jobs:
   # Check crate compiles and base cargo check passes
   linux-build-lib:
@@ -740,7 +743,7 @@ jobs:
         with:
           submodules: true
           fetch-depth: 1
-          
+
       - name: Mark repository as safe for git
         # Required for git commands inside container (avoids "dubious ownership" error)
         run: git config --global --add safe.directory "$GITHUB_WORKSPACE"