test_runner: support test order randomization #3275

Job	Run time
Build slim tarball	2m 8s
aarch64-linux: with shared libraries	39m 44s
x86_64-darwin: with shared libraries	1h 13m 37s
aarch64-darwin: with shared libraries	59m 2s
x86_64-linux: with shared libraries	47m 43s
	3h 42m 14s

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