Bump google.golang.org/grpc from 1.30.0 to 1.31.0 (#300)

Bumps [google.golang.org/grpc](https://github.com/grpc/grpc-go) from 1.30.0 to 1.31.0.
- [Release notes](https://github.com/grpc/grpc-go/releases)
- [Commits](grpc/grpc-go@v1.30.0...v1.31.0)

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

@@ -47,5 +47,5 @@ require (
 	golang.org/x/sys v0.0.0-20200428200454-593003d681fa // indirect
 	golang.org/x/tools v0.0.0-20200221224223-e1da425f72fd
 	google.golang.org/genproto v0.0.0-20200428115010-c45acf45369a
-	google.golang.org/grpc v1.30.0
+	google.golang.org/grpc v1.31.0
 )

go.sum

@@ -509,6 +509,8 @@ google.golang.org/grpc v1.29.1 h1:EC2SB8S04d2r73uptxphDSUG+kTKVgjRPF+N3xpxRB4=
 google.golang.org/grpc v1.29.1/go.mod h1:itym6AZVZYACWQqET3MqgPpjcuV5QH3BxFS3IjizoKk=
 google.golang.org/grpc v1.30.0 h1:M5a8xTlYTxwMn5ZFkwhRabsygDY5G8TYLyQDBxJNAxE=
 google.golang.org/grpc v1.30.0/go.mod h1:N36X2cJ7JwdamYAgDz+s+rVMFjt3numwzf/HckM8pak=
+google.golang.org/grpc v1.31.0 h1:T7P4R73V3SSDPhH7WW7ATbfViLtmamH0DKrP3f9AuDI=
+google.golang.org/grpc v1.31.0/go.mod h1:N36X2cJ7JwdamYAgDz+s+rVMFjt3numwzf/HckM8pak=
 google.golang.org/protobuf v0.0.0-20200109180630-ec00e32a8dfd/go.mod h1:DFci5gLYBciE7Vtevhsrf46CRTquxDuWsQurQQe4oz8=
 google.golang.org/protobuf v0.0.0-20200221191635-4d8936d0db64/go.mod h1:kwYJMbMJ01Woi6D6+Kah6886xMZcty6N08ah7+eCXa0=
 google.golang.org/protobuf v0.0.0-20200228230310-ab0ca4ff8a60/go.mod h1:cfTl7dwQJ+fmap5saPgwCLgHXTUD7jkjRqWcaiX5VyM=