build(deps): bump github.com/prometheus/client_golang (#4214)

Bumps [github.com/prometheus/client_golang](https://github.com/prometheus/client_golang) from 1.7.1 to 1.8.0.
- [Release notes](https://github.com/prometheus/client_golang/releases)
- [Changelog](https://github.com/prometheus/client_golang/blob/master/CHANGELOG.md)
- [Commits](https://github.com/prometheus/client_golang/compare/v1.7.1...v1.8.0)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

Co-authored-by: dependabot-preview[bot] <27856297+dependabot-preview[bot]@users.noreply.github.com>

go.mod

@@ -14,7 +14,7 @@ require (
 	github.com/dnstap/golang-dnstap v0.2.2
 	github.com/dustin/go-humanize v1.0.0 // indirect
 	github.com/farsightsec/golang-framestream v0.3.0
-	github.com/golang/protobuf v1.4.2
+	github.com/golang/protobuf v1.4.3
 	github.com/gorilla/websocket v1.4.0 // indirect
 	github.com/grpc-ecosystem/grpc-opentracing v0.0.0-20180507213350-8e809c8a8645
 	github.com/hashicorp/golang-lru v0.5.4 // indirect
@@ -26,13 +26,13 @@ require (
 	github.com/openzipkin-contrib/zipkin-go-opentracing v0.4.5
 	github.com/openzipkin/zipkin-go v0.2.2
 	github.com/philhofer/fwd v1.0.0 // indirect
-	github.com/prometheus/client_golang v1.7.1
+	github.com/prometheus/client_golang v1.8.0
 	github.com/prometheus/client_model v0.2.0
 	github.com/prometheus/common v0.14.0
 	go.etcd.io/etcd v0.5.0-alpha.5.0.20200306183522-221f0cc107cb
 	go.uber.org/zap v1.14.1 // indirect
 	golang.org/x/crypto v0.0.0-20201002170205-7f63de1d35b0
-	golang.org/x/sys v0.0.0-20200625212154-ddb9806d33ae
+	golang.org/x/sys v0.0.0-20201015000850-e3ed0017c211
 	google.golang.org/api v0.29.0
 	google.golang.org/grpc v1.29.1
 	gopkg.in/DataDog/dd-trace-go.v1 v1.27.1