A wrapper over Streamly.System.Command module (from streamly-process
package) to use sh as an interpreter for command strings. This package
just adds sh -c to a command to run it using shell. We can use
Streamly.System.Command directly instead. That we could use any shell
e.g. bash -c.
This is not part of the streamly-process package because this is POSIX
only and streamly-process is portable.