如何让Node.js忽略CSS文件，解决Mocha测试的扩展名报错问题

在原生JavaScript（vanilla JavaScript）项目中，当代码导入CSS文件后，使用Mocha运行测试时会失败，原因是Node.js无法忽略.css文件扩展名，抛出以下错误：

TypeError [ERR_UNKNOWN_FILE_EXTENSION]: Unknown file extension ".css"
    at new NodeError (node:internal/errors:405:5)
    at Object.getFileProtocolModuleFormat [as file:] (node:internal/modules/esm/get_format:79:11)
    at defaultGetFormat (node:internal/modules/esm/get_format:124:36)
    at defaultLoad (node:internal/modules/esm/load:84:20)
    at nextLoad (node:internal/modules/esm/loader:163:28)
    at ESMLoader.load (node:internal/modules/esm/loader:603:26)
    at ESMLoader.moduleProvider (node:internal/modules/esm/loader:457:22)
    at new ModuleJob (node:internal/modules/esm/module_job:64:26)
    at #createModuleJob (node:internal/modules/esm/loader:480:17)
    at ESMLoader.getModuleJob (node:internal/modules/esm/loader:434:34)
    at async ModuleWrap.<anonymous> (node:internal/modules/esm/module_job:79:21)

目前找到的相关解决方案均已过时，无法解决该问题。存在一个可复现该问题的示例仓库。

内容的提问来源于stack exchange，提问作者Marco Crisostomi