Within the `sh` package, args are being expanded in the case where normal sh command would not expand args within single quotes. Example command: `pact-broker create-webhook --user='admin:${user.bitbucketAppPassword}'` 1. Via normal shell the single quotes will not expand `${user.bitbucketAppPassword}` 2. Via mage the expansion occurs and the actual command becomes: `pact-broker create-webhook --user='admin:'` https://github.com/magefile/mage/blob/26cdb5c7369a9b03981eb906dd3606c566e45c16/sh/cmd.go#L92-L115