Added OpenSSH server to the SSH docs

[nguyen-dows]

Made ssh.md to be inclusive of OpenSSH server since the steps to find it are the same as OpenSSH client. This closes #736

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

Learn Build status updates of commit 93f0b30:

:white_check_mark: Validation status: passed

File	Status	Preview URL	Details
TerminalDocs/tutorials/media/ssh/ssh-optionalfeature.png	:white_check_mark:Succeeded	View
TerminalDocs/tutorials/ssh.md	:white_check_mark:Succeeded	View

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

Learn Build status updates of commit 33190aa:

:white_check_mark: Validation status: passed

File	Status	Preview URL	Details
TerminalDocs/images/ssh-optionalfeature.png	:white_check_mark:Succeeded	View
TerminalDocs/images/ssh-optonialfeatures.png	:white_check_mark:Succeeded	n/a (file deleted or renamed)
TerminalDocs/tutorials/media/ssh/ssh-optionalfeature.png	:white_check_mark:Succeeded	View
TerminalDocs/tutorials/ssh.md	:white_check_mark:Succeeded	View

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

Learn Build status updates of commit a76c67f:

:white_check_mark: Validation status: passed

File	Status	Preview URL	Details
TerminalDocs/images/ssh-optonialfeatures.png	:white_check_mark:Succeeded	n/a (file deleted or renamed)
TerminalDocs/tutorials/media/ssh/ssh-optionalfeature.png	:white_check_mark:Succeeded	View
TerminalDocs/tutorials/ssh.md	:white_check_mark:Succeeded	View

For more details, please refer to the build report.

For any questions, please:

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• Post your question in the Learn support channel