Update gRPC version to v1.29.1 (#654)

go.mod

@@ -63,7 +63,7 @@ require (
 	golang.org/x/tools v0.0.0-20191105231337-689d0f08e67a
 	google.golang.org/appengine v1.6.1 // indirect
 	google.golang.org/genproto v0.0.0-20200402124713-8ff61da6d932
-	google.golang.org/grpc v1.28.1
+	google.golang.org/grpc v1.29.1
 	gopkg.in/go-playground/assert.v1 v1.2.1 // indirect
 	gopkg.in/go-playground/validator.v9 v9.29.1
 	gopkg.in/yaml.v2 v2.2.8

go.sum

@@ -474,6 +474,8 @@ google.golang.org/grpc v1.26.0/go.mod h1:qbnxyOmOxrQa7FizSgH+ReBfzJrCY1pSN7KXBS8
 google.golang.org/grpc v1.27.0/go.mod h1:qbnxyOmOxrQa7FizSgH+ReBfzJrCY1pSN7KXBS8abTk=
 google.golang.org/grpc v1.28.1 h1:C1QC6KzgSiLyBabDi87BbjaGreoRgGUF5nOyvfrAZ1k=
 google.golang.org/grpc v1.28.1/go.mod h1:rpkK4SK4GF4Ach/+MFLZUBavHOvF2JJB5uozKKal+60=
+google.golang.org/grpc v1.29.1 h1:EC2SB8S04d2r73uptxphDSUG+kTKVgjRPF+N3xpxRB4=
+google.golang.org/grpc v1.29.1/go.mod h1:itym6AZVZYACWQqET3MqgPpjcuV5QH3BxFS3IjizoKk=
 gopkg.in/alecthomas/kingpin.v2 v2.2.6/go.mod h1:FMv+mEhP44yOT+4EoQTLFTRgOQ1FBLkstjWtayDeSgw=
 gopkg.in/bsm/ratelimit.v1 v1.0.0-20160220154919-db14e161995a/go.mod h1:KF9sEfUPAXdG8Oev9e99iLGnl2uJMjc5B+4y3O7x610=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=