CometMock tests fail randomly

[p-offtermatt]

Summary of Bug

Tests using CometMock seem to fail nondeterministically, with or without error messages.
Some failure logs are here:

https://gist.github.com/p-offtermatt/4294dd21755381ef0bc190bbeb208a7c

Version

Various

Steps to Reproduce

Run go run ./tests/e2e/main.go --tc happy-path-short --use-cometmock --use-gorelayer --verbose multiple times (~10 should do it, from empirical experience) until you get a test failure.

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[p-offtermatt]

This should be fixed per informalsystems/CometMock#35, see that PR for more context