Bug#843453: apt-file: Typo in 60disable-contents-fetching.conf

[Felix Geyer]

Package: apt-file
Version: 3.1.3

There's a typo in 
/usr/share/doc/apt-file/examples/60disable-contents-fetching.conf

In a comment it says "[targets+=Contents-deb]" instead of 
"[target+=Contents-deb]"