async findConfigFileForPath(fileOrDirPath) {
		assertValidFilePath(fileOrDirPath);

		const absoluteDirPath = path.resolve(
			this.#options.cwd,
			path.dirname(fileOrDirPath),
		);
		const { configFilePath } =
			await this.#locateConfigFileToUse(absoluteDirPath);

		return configFilePath;
	}
Returns the config file path for the given directory or file. This will either use
the override config file that was specified in the constructor options or
search for a config file from the directory.
@param {string} fileOrDirPath The file or directory path to get the config file path for.
@returns {Promise<string|undefined>} The config file path or `undefined` if not found.
@throws {Error} If `fileOrDirPath` is not a non-empty string.
@throws {Error} If `fileOrDirPath` is not an absolute path.