ci: 修复 GitHub Actions 中上传构建产物的路径格式

修复了 `cmake-single-platform.yml` 文件中 `path` 字段的格式问题，确保构建产物 `kernel.iso` 和 `test.img` 能够正确上传

Author: zhangfuwen

.github/workflows/cmake-single-platform.yml

@@ -42,9 +42,9 @@ jobs:
       uses: actions/[email protected]
       with:
         name: build-artifacts
-        path: 
-          - ${{github.workspace}}/build/kernel.iso
-          - ${{github.workspace}}/build/test.img
+        path: |
+          ${{github.workspace}}/build/kernel.iso
+          ${{github.workspace}}/build/test.img
         if-no-files-found: error
         compression-level: 6
         overwrite: true