Multiple exporter responses #5994

Job	Run time
build (windows/amd64)	1m 46s
build (freebsd/amd64)	1m 45s
sandbox-build (linux/amd64)	6m 55s
sandbox-build (linux/arm64)	4m 41s
test-freebsd-amd64	2m 27s
test-windows-amd64 (containerd, ./client)	7m 7s
test-windows-amd64 (containerd, ./cmd/buildctl)	3m 6s
test-windows-amd64 (containerd, ./worker/containerd)	3m 34s
test-windows-amd64 (containerd, ./solver)	2m 32s
test-windows-amd64 (containerd, ./frontend)	3m 9s
test-windows-amd64 (containerd, ./frontend/dockerfile)	39m 44s
test-windows-amd64 (./..., 1)	4m 33s
	1h 21m 19s

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