Exclude jstests/core/autocomplete.js from sharded jscore tests

The methods returned by autocomplete.js are being interpreted as collections and are implicitly sharded.
To prevent the BF, for now, we can just exclude the autocomple.js from the test with the getCollection overload.
There are 2 questions still open:

• what calls getCollection on the list returned in _autocomplete_
• why this list sometimes includes viewSource method that causes the BF