src/encoded/tests/conftest.py: remove the unused 'config' fixture.
src/encoded/tests/conftest.py: remove the unused 'config' fixture.

4dn-dcic/fourfront,hms-dbmi/fourfront,4dn-dcic/fourfront,4dn-dcic/fourfront,4dn-dcic/fourfront,hms-dbmi/fourfront,hms-dbmi/fourfront,hms-dbmi/fourfront,hms-dbmi/fourfront