fix: usage of `node12 which is deprecated` (#335)

.github/workflows/sync.yml

@@ -15,7 +15,7 @@ jobs:
     - name: Get repo name
       run: R=${GITHUB_REPOSITORY%?wiki}; echo "BASENAME=${R##*/}" >> $GITHUB_ENV
     - name: Checkout ${{ env.BASENAME }}-wiki
-      uses: actions/checkout@v2
+      uses: actions/checkout@v4
       with:
         repository: "${{ GITHUB.repository_owner }}/${{ env.BASENAME }}-wiki"
         token: ${{ secrets.TS_BOT_TOKEN }}