fix querycache in rails 5 when prepared statements are disabled
fix querycache in rails 5 when prepared statements are disabled

Change-Id: I6e75482d0dacb146da595434ea8a29bd05aef242
Reviewed-on: https://gerrit.instructure.com/89152
Tested-by: Jenkins
Reviewed-by: Dan Minkevitch <2591e5f46f28d303f9dc027d475a5c60d8dea17a@instructure.com>
Product-Review: Cody Cutrer <c4fe2b1d90ef8f2548c8aeabfa633434316f0305@instructure.com>
QA-Review: Cody Cutrer <c4fe2b1d90ef8f2548c8aeabfa633434316f0305@instructure.com>

instructure/switchman,instructure/switchman