在linux（TravisCI环境）中运行Java / Selenium测试用例时，出现以下错误。需要帮助。
Constructor threw exception; nested exception is
org.openqa.selenium.WebDriverException: unknown error: Chrome
failed to
start: exited abnormally
(Driver info: chromedriver=2.30.477691
(6ee44a7247c639c0703f291d320bdf05c1531b57),platform=Linux 4.4.0-
101-generic x86_64) (WARNING: The server did not provide any
stacktrace information)