Bump google.golang.org/grpc from 1.53.0 to 1.56.3

Bumps [google.golang.org/grpc](https://github.com/grpc/grpc-go) from 1.53.0 to 1.56.3.
- [Release notes](https://github.com/grpc/grpc-go/releases)
- [Commits](grpc/grpc-go@v1.53.0...v1.56.3)

---
updated-dependencies:
- dependency-name: google.golang.org/grpc
  dependency-type: direct:production
...

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

go.mod

@@ -25,8 +25,8 @@ require (
 	github.com/tiago4orion/conjure v0.0.0-20150908101743-93cb30b9d218 // indirect
 	github.com/yl2chen/cidranger v1.0.2
 	golang.org/x/sync v0.1.0
-	google.golang.org/grpc v1.53.0
-	google.golang.org/protobuf v1.28.1
+	google.golang.org/grpc v1.56.3
+	google.golang.org/protobuf v1.30.0
 	gopkg.in/mgo.v2 v2.0.0-20190816093944-a6b53ec6cb22
 	gopkg.in/pg.v5 v5.3.3
 )