Add quotes to zzz.sh and replace legacy backticks with $()

[bcr]

Summary

This patch does the following:

• Replaces legacy backticks with $()
• Quote strings to prevent word splitting

Test Plan

The changes should not affect the code execution, but I found no tests for zzz that I could run.

[imp]

usr.sbin/zzz/zzz.sh

21

You can kill the space before the ).

[bcr]

Thanks for the feedback. I removed the extra whitespace at the line you mentioned and in another instance further down.

[imp]

I'm bothered by the pre existing echo grep pair.
But these cleanups do make the code marginally better...