Fix docker run command

[FantasqueX]

Current one will get error "/usr/bin/ls: /usr/bin/ls: cannot execute binary file"

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

Learn Build status updates of commit 918347d:

:white_check_mark: Validation status: passed

File	Status	Preview URL	Details
WSL/use-custom-distro.md	:white_check_mark:Succeeded	View

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[mattwojo]

Thanks for the fix @FantasqueX!