spec: add test for user btn non-existence
spec: add test for user btn non-existence

TEST PLAN
- Code Review

Change-Id: I3e82a8571b25892dc565474737a3fc5bcf73638a
Reviewed-on: https://gerrit.instructure.com/84077
Tested-by: Jenkins
Reviewed-by: Pedro Fajardo <121b528f0c2f2e923ce3103793aca31b9a662ac4@instructure.com>
Product-Review: Caleb Guanzon <54fa1f30d451e4f3c341a8f3c47c9215fd0be9c6@instructure.com>
QA-Review: Caleb Guanzon <54fa1f30d451e4f3c341a8f3c47c9215fd0be9c6@instructure.com>

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