Shrink on one worker #1962

Job	Run time
Build Echidna on ubuntu-20.04	5m 17s
Build Echidna on macos-13	7m 10s
Build Echidna on windows-latest	14m 25s
Test with solc 0.4.25 on ubuntu-latest	4m 42s
Test with solc 0.5.7 on ubuntu-latest	4m 26s
Test with solc 0.6.12 on ubuntu-latest	3m 36s
Test with solc 0.7.5 on ubuntu-latest	3m 58s
Test with solc 0.4.25 on windows-latest	4m 0s
Test with solc 0.5.7 on windows-latest	4m 30s
Test with solc 0.6.12 on windows-latest	3m 31s
Test with solc 0.7.5 on windows-latest	4m 53s
	1h 0m 28s

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