What is the ruling on the imam's saying in the Friday sermon, "And I bear witness that Muhammad is the Messenger of Allah, who delivered the message, fulfilled the trust, advised the Ummah, and dispelled the gloom," and is it permissible to say "dispelled the gloom"?

There is no harm in the phrase "Kashf al-Ghumma" (removing the distress) when mentioning the Prophet, peace and blessings be upon him. Many scholars have used it, such as Ibn Taymiyyah, Al-Khatib al-Baghdadi, and Ibn al-'Imad al-Hanbali. Attributing the removal of distress to him is only by virtue of Allah the Almighty being the One who removed the distress through him and dispelled the darkness of polytheism through him.