Makefile: Don't read COMMIT, BUILDTAGS, EXTRA_BUILDTAGS from env vars #6482

Job	Run time
cross-i386	1m 22s
cross-i386 (runc_nodmz)	1m 44s
test (ubuntu-20.04, 1.22.x, rootless, -race)	7m 14s
test (ubuntu-20.04, 1.22.x, rootless)	6m 53s
test (ubuntu-20.04, 1.22.x, -race)	8m 12s
test (ubuntu-20.04, 1.22.x)	7m 4s
test (ubuntu-20.04, 1.23.x, rootless, -race)	7m 24s
test (ubuntu-20.04, 1.23.x, rootless)	6m 46s
test (ubuntu-20.04, 1.23.x, -race)	8m 2s
test (ubuntu-20.04, 1.23.x)	7m 14s
test (ubuntu-20.04, 1.23.x, criu-dev)	7m 51s
test (ubuntu-24.04, 1.22.x, rootless, -race)	9m 24s
test (ubuntu-24.04, 1.22.x, rootless)	9m 7s
test (ubuntu-24.04, 1.22.x, -race)	8m 14s
test (ubuntu-24.04, 1.22.x)	7m 21s
test (ubuntu-24.04, 1.23.x, rootless, -race)	9m 36s
test (ubuntu-24.04, 1.23.x, rootless)	9m 15s
test (ubuntu-24.04, 1.23.x, -race)	8m 1s
test (ubuntu-24.04, 1.23.x)	7m 28s
test (ubuntu-24.04, 1.23.x, runc_nodmz)	7m 27s
test (ubuntu-24.04, 1.23.x, criu-dev)	8m 15s
test (actuated-arm64-6cpu-8gb, 1.23.x, rootless)	11m 39s
test (actuated-arm64-6cpu-8gb, 1.23.x)	8m 42s
all-done	1s
	2h 54m 16s

Provide feedback