Fix compiled-in /bin/bash in foomatic filters

Foomatic filters contained a 64-char c string hardcoded to /bin/bash.
This caused some filters (at least pdftops) to fail.

I also had to increase the size of the string because nix paths are too
long.
squish cups patches all into one statement
Merge pull request #5428 from bdimcheff/fix-cups-filter-bash

Fix compiled-in /bin/bash in foomatic filters