test_runner: support test order randomization #3296

Job	Run time
Build slim tarball	2m 22s
aarch64-linux: with shared libraries	1h 23m 40s
aarch64-darwin: with shared libraries	1h 41m 16s
x86_64-darwin: with shared libraries	2h 40m 27s
x86_64-linux: with shared libraries	1h 58m 26s
	7h 46m 11s

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