show trace on UnknownFailure (#1283) #1975

Job	Run time
Build Echidna on ubuntu-20.04	5m 35s
Build Echidna on macos-13	9m 28s
Build Echidna on windows-latest	28m 53s
Test with solc 0.4.25 on ubuntu-latest	4m 42s
Test with solc 0.5.7 on ubuntu-latest	3m 36s
Test with solc 0.6.12 on ubuntu-latest	3m 31s
Test with solc 0.7.5 on ubuntu-latest	3m 42s
Test with solc 0.4.25 on windows-latest	4m 19s
Test with solc 0.5.7 on windows-latest	4m 12s
Test with solc 0.6.12 on windows-latest	4m 42s
Test with solc 0.7.5 on windows-latest	4m 55s
	1h 17m 35s

Provide feedback