Fix Command Prompt's `title` usage in tab-title.md

[mataha]

It doesn't ignore quotes, but incorporates them into the new title.

The following command:

> title "New Title"

will set the shell's title to "New Title". A better alternative:

> (title^ New Title)

Though this might be too arcane for the purposes of that document.

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

Learn Build status updates of commit 5b0e5a9:

:white_check_mark: Validation status: passed

File	Status	Preview URL	Details
TerminalDocs/tutorials/tab-title.md	:white_check_mark:Succeeded	View

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