fix plz edge case

[AnEmortalKid]

Fixes an edge case with plz.

plz foo with {'Content-Type': 'text/plain'} {'Accept': 'en-US'} {'X-Other': 'oh-bother'}

Used to convert to:

foo ( {'Content-Type': 'text/plain'}, {'Accept': 'en-US', }, {'X-Other': 'oh-bother', }

There was code to handle converting , } into } but it only did it once, so I changed it to repeat that fix.