allow rails 6.1
allow rails 6.1

Change-Id: I1972152665680548e6ea176333ca8a2c6b3ae574
Reviewed-on: https://gerrit.instructure.com/c/academic_benchmarks/+/265606
Tested-by: Service Cloud Jenkins <9144042a601061f88f1e1d7a1753ea3e2972119d@instructure.com>
Reviewed-by: Jacob Burroughs <8ecea6e385af5cf9f53123f5ca17fb5fd6a6d4b2@instructure.com>
QA-Review: Cody Cutrer <c4fe2b1d90ef8f2548c8aeabfa633434316f0305@instructure.com>
Product-Review: Cody Cutrer <c4fe2b1d90ef8f2548c8aeabfa633434316f0305@instructure.com>

instructure/academic_benchmarks,instructure/academic_benchmarks