ci: fix actions/cache version

Author: kilemensi

.github/workflows/ci.yml

@@ -45,7 +45,7 @@ jobs:
           echo "STORE_PATH=$(pnpm store path)" >> $GITHUB_OUTPUT
 
       - name: Setup pnpm cache
-        uses: actions/cache@v6
+        uses: actions/cache@v5
         with:
           path: ${{ steps.pnpm-cache.outputs.STORE_PATH }}
           key: ${{ runner.os }}-pnpm-store-${{ hashFiles('**/pnpm-lock.yaml') }}