Bump github.com/golang/protobuf (#728)

Bumps [github.com/golang/protobuf](https://github.com/golang/protobuf) from 1.5.1 to 1.5.2.
- [Release notes](https://github.com/golang/protobuf/releases)
- [Commits](golang/protobuf@v1.5.1...v1.5.2)

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

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: Tyler Yahn <MrAlias@users.noreply.github.com>

instrumentation/google.golang.org/grpc/otelgrpc/example/go.mod

@@ -8,7 +8,7 @@ replace (
 )
 
 require (
-	github.com/golang/protobuf v1.5.1
+	github.com/golang/protobuf v1.5.2
 	go.opentelemetry.io/contrib/instrumentation/google.golang.org/grpc/otelgrpc v0.19.0
 	go.opentelemetry.io/otel v0.19.0
 	go.opentelemetry.io/otel/exporters/stdout v0.19.0

instrumentation/google.golang.org/grpc/otelgrpc/example/go.sum

@@ -24,8 +24,9 @@ github.com/golang/protobuf v1.4.0/go.mod h1:jodUvKwWbYaEsadDk5Fwe5c77LiNKVO9IDvq
 github.com/golang/protobuf v1.4.1/go.mod h1:U8fpvMrcmy5pZrNK1lt4xCsGvpyWQ/VVv6QDs8UjoX8=
 github.com/golang/protobuf v1.4.2/go.mod h1:oDoupMAO8OvCJWAcko0GGGIgR6R6ocIYbsSw735rRwI=
 github.com/golang/protobuf v1.5.0/go.mod h1:FsONVRAS9T7sI+LIUmWTfcYkHO4aIWwzhcaSAoJOfIk=
-github.com/golang/protobuf v1.5.1 h1:jAbXjIeW2ZSW2AwFxlGTDoc2CjI2XujLkV3ArsZFCvc=
 github.com/golang/protobuf v1.5.1/go.mod h1:DopwsBzvsk0Fs44TXzsVbJyPhcCPeIwnvohx4u74HPM=
+github.com/golang/protobuf v1.5.2 h1:ROPKBNFfQgOUMifHyP+KYbvpjbdoFNs+aK7DXlji0Tw=
+github.com/golang/protobuf v1.5.2/go.mod h1:XVQd3VNwM+JqD3oG2Ue2ip4fOMUkwXdXDdiuN0vRsmY=
 github.com/google/go-cmp v0.2.0/go.mod h1:oXzfMopK8JAjlY9xF4vHSVASa0yLyX7SntLO5aqRK0M=
 github.com/google/go-cmp v0.3.0/go.mod h1:8QqcDgzrUqlUb/G2PQTWiueGozuR1884gddMywk6iLU=
 github.com/google/go-cmp v0.3.1/go.mod h1:8QqcDgzrUqlUb/G2PQTWiueGozuR1884gddMywk6iLU=