spec: add retries to failing specs
spec: add retries to failing specs

Closes LS-3215

Test Plan: passes jenkins, especially this dashboard teacher spec

Change-Id: I374019f1c6f360c48487c017e85944d0f211ba3e
Reviewed-on: https://gerrit.instructure.com/c/canvas-lms/+/295908
Tested-by: Service Cloud Jenkins <9144042a601061f88f1e1d7a1753ea3e2972119d@instructure.com>
Reviewed-by: Jackson Howe <318c10a818c1b1f2ec50cdcb1827b2c6c5ebd7dc@instructure.com>
QA-Review: Jackson Howe <318c10a818c1b1f2ec50cdcb1827b2c6c5ebd7dc@instructure.com>
Product-Review: Robin Kuss <0b206b54367b2de0334896ea45826f0e3194bd35@instructure.com>

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