Update deploy.yml

そもそもcpが間違っていた

.github/workflows/deploy.yml

@@ -37,10 +37,10 @@ jobs:
           cache: 'npm'
       - name: Install dependencies
         run: npm ci
-      - name: 404 Page
-        run: cp ./404.html ./public/404.html　
       - name: Build
         run: npm run build
+      - name: 404 Page
+        run: cp ./dist/index.html　./dist/404.html 
       - name: Setup Pages
         uses: actions/configure-pages@v4
       - name: Upload artifact