Revert "ask the fixture set for the sql statements"

This reverts commit 026d0555685087845b74dd87a0417b5a164b1c13.

Conflicts:
	activerecord/lib/active_record/fixtures.rb

Fixes #13383
Merge branch 'master' into ruby-2.2

* master:
  Revert "ask the fixture set for the sql statements"