Fixed typo (AI Chat to Terminal Chat)

[nguyen-dows]

This PR fixes a typo in the Actions Tips & Tricks and updates a screenshot.

[learn-build-service-prod[bot]]

Learn Build status updates of commit faaaeb1:

:white_check_mark: Validation status: passed

File	Status	Preview URL	Details
TerminalDocs/images/terminal-chat-action.png	:white_check_mark:Succeeded	View
TerminalDocs/terminal-chat.md	:white_check_mark:Succeeded	View

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