Add note about Profile index adjustments

[thadguidry]

FIXES #768 There is currently no documentation about "profile index" and actually how to adjust this or what affects it. The "profile index" directly affects the key combo to launch, such as Ctrl+Shift+1

• This helps tell users how to adjust the index numbering, and hence control the assigned key combo to launch.

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

Learn Build status updates of commit 7252294:

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

Learn Build status updates of commit 2ee4c68:

:white_check_mark: Validation status: passed

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

Learn Build status updates of commit 16c798b:

:white_check_mark: Validation status: passed

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TerminalDocs/customize-settings/profile-general.md	:white_check_mark:Succeeded	View

For more details, please refer to the build report.

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[nguyen-dows]

Hi @thadguidry, I made a few small formatting changes to your PR and merged it in! Thank you SO MUCH for the help on this! :)