[exporter/signalfx] hostmetadata fails to compile on multiple platforms

[jpkrohling]

When building the contrib distribution as part of the releases repository, the signalfx exporter fails to compile, due to:

Error: /home/runner/go/pkg/mod/github.com/open-telemetry/opentelemetry-collector-contrib/exporter/[email protected]/internal/hostmetadata/host_linux.go:37:68: cannot use uname.Version[:] (type []uint8) as type []int8 in argument to int8ArrayToByteArray
Error: /home/runner/go/pkg/mod/github.com/open-telemetry/opentelemetry-collector-contrib/exporter/[email protected]/internal/hostmetadata/host_linux.go:47:62: cannot use uname.Machine[:] (type []uint8) as type []int8 in argument to int8ArrayToByteArray

cc @pmcollins @asuresh4 @dmitryax

[jpkrohling]

Note: I was able to run goreleaser locally without problems, so, not sure this is happening only in the CI.

[jpkrohling]

Same with s390x:

   ⨯ release failed after 167.48s error=failed to build for linux_s390x: exit status 2: # github.com/open-telemetry/opentelemetry-collector-contrib/exporter/signalfxexporter/internal/hostmetadata
/home/jpkroehling/go/pkg/mod/github.com/open-telemetry/opentelemetry-collector-contrib/exporter/[email protected]/internal/hostmetadata/host_linux.go:37:68: cannot use uname.Version[:] (type []uint8) as type []int8 in argument to int8ArrayToByteArray
/home/jpkroehling/go/pkg/mod/github.com/open-telemetry/opentelemetry-collector-contrib/exporter/[email protected]/internal/hostmetadata/host_linux.go:47:62: cannot use uname.Machine[:] (type []uint8) as type []int8 in argument to int8ArrayToByteArray

make: *** [Makefile:27: goreleaser-verify] Error 1

[jpkrohling]

And armv7:

   ⨯ release failed after 10.31s error=failed to build for linux_arm_7: exit status 2: # github.com/open-telemetry/opentelemetry-collector-contrib/exporter/signalfxexporter/internal/hostmetadata
/home/jpkroehling/go/pkg/mod/github.com/open-telemetry/opentelemetry-collector-contrib/exporter/[email protected]/internal/hostmetadata/host_linux.go:37:68: cannot use uname.Version[:] (type []uint8) as type []int8 in argument to int8ArrayToByteArray
/home/jpkroehling/go/pkg/mod/github.com/open-telemetry/opentelemetry-collector-contrib/exporter/[email protected]/internal/hostmetadata/host_linux.go:47:62: cannot use uname.Machine[:] (type []uint8) as type []int8 in argument to int8ArrayToByteArray

[dmitryax]

I was able to reproduce it with otel builder. Will submit a PR shortly