[Testing:TAGrading] Next/Prev e2e tests (#5766)
[Testing:TAGrading] Next/Prev e2e tests (#5766)

* first draft tests

* undoing base changes

* adding tests

* reverting change

* removing from travis

* adding missing import

* test fixes

Co-authored-by: unknown <f6785f40afc5de295e70b6210e68542c2d24cb5b@rpi.edu>
Co-authored-by: Barb Cutler <b4fc851c82a06ed3e5f5c72e00b8d2b8b8ad995c@users.noreply.github.com>
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