Update update-letter.yml

updated action versions

.github/workflows/update-letter.yml

@@ -13,12 +13,12 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
       with:
         persist-credentials: false # otherwise, the token used is the GITHUB_TOKEN, instead of your personal token
         fetch-depth: 0 # otherwise, you will failed to push refs to dest repo    
     - name: Set up Python 3.10
-      uses: actions/setup-python@v3
+      uses: actions/setup-python@v5
       with:
         python-version: "3.10"
     - name: Install dependencies