chore: 移除 workflow 中已棄用的 --no-suggest 參數

Composer 2.0+ 中 --no-suggest 參數已被棄用並移除。
此更新確保 CI/CD 流程與 Laravel 6 和現代 Composer 版本兼容。

Author: claude

.github/workflows/phpunit.yml

@@ -29,7 +29,7 @@ jobs:
           coverage: none
 
       - name: Install dependencies
-        run: composer install --prefer-dist --no-progress --no-suggest
+        run: composer install --prefer-dist --no-progress
 
       - name: Prepare environment
         run: |