add test feature flag
add test feature flag

refs DE-1201

Change-Id: I6f913cc310418863e5c04d793ac3c721d8e567f8
Reviewed-on: https://gerrit.instructure.com/c/canvas-lms/+/292212
Reviewed-by: Isaac Moore <258108225390078ef47d1319acab49ad7948abf1@instructure.com>
QA-Review: Aaron Ogata <11ccf682c06d1508642f943a3962a1c3d00b8e44@instructure.com>
Product-Review: Aaron Ogata <11ccf682c06d1508642f943a3962a1c3d00b8e44@instructure.com>
Tested-by: Service Cloud Jenkins <9144042a601061f88f1e1d7a1753ea3e2972119d@instructure.com>

sfu/canvas-lms,sfu/canvas-lms,sfu/canvas-lms,sfu/canvas-lms,sfu/canvas-lms,sfu/canvas-lms,sfu/canvas-lms