CI: Fix and migrate the testsuite part to Testing Farm #618

Job	Run time
build (gcc, 3.13, 3.3)	2m 5s
build (gcc, 3.13, 3.3, test-flags-override)	1m 38s
build (gcc, 3.13, 3.3, test-debug)	1m 43s
build (gcc, 3.13, 3.3, linker-bfd)	2m 0s
build (gcc, 3.13, 3.3, linker-gold)	1m 58s
build (gcc, 3.12, 3.3)	1m 46s
build (gcc, 3.11, 3.3)	1m 40s
build (gcc, 3.10, 3.3)	2m 11s
build (gcc, 3.9, 3.3)	1m 59s
build (gcc, 3.8, 3.3)	2m 11s
build (gcc, pypy3.7, 3.3)	2m 22s
build (gcc, 3.13, 3.2)	1m 54s
build (gcc, 3.13, 3.1)	1m 55s
build (gcc, 3.13, 3.0)	2m 9s
build (gcc, 3.13, 2.7)	2m 54s
build (gcc, 3.13, 2.6)	2m 9s
build (gcc, 3.13, 2.5)	2m 4s
build (clang, 3.13, 3.3)	2m 3s
build (clang, 3.13, 3.3, test-flags-override)	1m 46s
build (clang, 3.13, 3.3, test-debug)	1m 57s
build (clang, 3.12, 3.3)	2m 55s
build (clang, 3.11, 3.3)	2m 59s
build (clang, 3.10, 3.3)	1m 58s
build (clang, 3.9, 3.3)	2m 1s
build (clang, 3.8, 3.3)	2m 1s
build (clang, pypy3.7, 3.3)	2m 19s
build (clang, 3.13, 3.2)	1m 57s
build (clang, 3.13, 3.1)	2m 6s
build (clang, 3.13, 3.0)	1m 55s
build (clang, 3.13, 2.7)	2m 13s
build (clang, 3.13, 2.6)	2m 43s
build (clang, 3.13, 2.5)	2m 8s
build (gcc, 3.13, 3.3, sanitizers)	2m 34s
	1h 10m 13s

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