tests: make tests fail when baseline not found
tests: make tests fail when baseline not found

When baseline is not available, performance tests pass without any
errors. This commit makes tests fail in such situation. It lets us know
which performance baselines are missing.

Signed-off-by: Takahiro Itazuri <fcdc524496a9745e84aa44a21de7df82b8cefc09@amazon.com>

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