Add a tutorial for using the progress bar

[zadjii-msft]

As noted in #514

closes #514

xref microsoft/terminal#6700

[learn-build-service-prod]

Learn Build status updates of commit 6258810:

💡 Validation status: suggestions

File	Status	Preview URL	Details
TerminalDocs/tutorials/progress-bar-sequences.md	💡Suggestion	View	Details
TerminalDocs/TOC.yml	✅Succeeded	View

TerminalDocs/tutorials/progress-bar-sequences.md

• Line 0, Column 0: [Suggestion: external-image] Image 'https://devblogs.microsoft.com/commandline/wp-content/uploads/sites/33/2021/01/progress-ring.gif' references an external site. This poses a security risk and external images are unavailable in some environments. Reference an image file within the repo instead.

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