spec: refactor flaky dashcards_sepc.rb
spec: refactor flaky dashcards_sepc.rb

Change-Id: I5ce237fb202c7d816c55207f499bf22c5ef02f82
Fixes: QA-603
Reviewed-on: https://gerrit.instructure.com/169802
Tested-by: Jenkins
Reviewed-by: Derek Bender <d24d8a7ee520e34b1cec38800225d9f36b552df7@instructure.com>
QA-Review: Anju Reddy <851202533fb1f0b615e4547ba226c76996d060dd@instructure.com>
Product-Review: Anju Reddy <851202533fb1f0b615e4547ba226c76996d060dd@instructure.com>

sfu/canvas-lms,djbender/canvas-lms,sfu/canvas-lms,instructure/canvas-lms,sfu/canvas-lms,instructure/canvas-lms,instructure/canvas-lms,sfu/canvas-lms,djbender/canvas-lms,instructure/canvas-lms,sfu/canvas-lms,instructure/canvas-lms,djbender/canvas-lms,instructure/canvas-lms,sfu/canvas-lms,instructure/canvas-lms,sfu/canvas-lms,djbender/canvas-lms