Upstream gotestsum changes used by acc test suite

[ddelnano]

In #188, I decided to modify gotestsum in order to allow it to rerun tests that have panic'ed (ddelnano/gotestsum@8c70ff0). This is common in the acceptance test suite because many of the VM tests take a long time to run and result in flaky builds due to the timeouts.

We should upstream these changes so that it isn't required to use my fork of the gotestsum repository long term. From my work in this space, gotestsum has a history of dealing with go's timeout panic behavior (gotestyourself/gotestsum#192, golang/go#45508, golang/go#38382). The maintainer of the project has disabled this behavior, but I'm hopeful it would be accepted behind a runtime toggle.

[ddelnano]

I've created an issue to inquire if this contribution would be accepted (gotestyourself/gotestsum#290)

[ddelnano]

This is no longer needed.