tests: Search path for bash
tests: Search path for bash

Bash on BSDs is not in /bin.

Fixes bug 644876.

frida/vala,spidermonkdust/vala,frida/vala,playya/vala,rvu95/vala,kamanashisroy/aroop,flobrosch/vala-fixes,jessevdk/vala,jessevdk/vala,kamanashisroy/aroop,severinh/vala,flobrosch/vala-fixes,Distrotech/vala,frida/vala,frida/vala,spidermonkdust/vala,GNOME/vala,tjol/vala-tjol,Distrotech/vala,Distrotech/vala,GNOME/vala,flobrosch/vala-fixes,playya/vala,GNOME/vala,severinh/vala,jessevdk/vala,xdave/pvala,tjol/vala-tjol,rvu95/vala,tjol/vala-tjol,frida/vala,playya/vala,kamanashisroy/aroop,spidermonkdust/vala,rvu95/vala,severinh/vala,GNOME/vala