Flaky Test: TestUpdateGasPriceInitializesPrice

[aaronbuchwald]

Describe the bug
The following test flakes sometimes in CI: https://github.com/ava-labs/subnet-evm/actions/runs/4106650918/jobs/7085148883#step:6:55

Expected behavior
The test should pass consistently.

Screenshots

[aaronbuchwald]

The bug is here: https://github.com/ava-labs/subnet-evm/blob/master/plugin/evm/gasprice_update_test.go#L41-L57

The attemptWait function starts a goroutine to wait for a waitgroup to finish and then close a channel. However, this creates a race condition because that goroutine may finish after the passed in ticker has already gone off to signal that the test has timed out and should fail

[aaronbuchwald]

Fixed by #514