rebase: bump google.golang.org/grpc from 1.49.0 to 1.50.1

Bumps [google.golang.org/grpc](https://github.com/grpc/grpc-go) from 1.49.0 to 1.50.1.
- [Release notes](https://github.com/grpc/grpc-go/releases)
- [Commits](https://github.com/grpc/grpc-go/compare/v1.49.0...v1.50.1)

---
updated-dependencies:
- dependency-name: google.golang.org/grpc
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

vendor/google.golang.org/grpc/internal/resolver/unix/unix.go

@@ -49,8 +49,9 @@ func (b *builder) Build(target resolver.Target, cc resolver.ClientConn, _ resolv
 	}
 	addr := resolver.Address{Addr: endpoint}
 	if b.scheme == unixAbstractScheme {
-		// prepend "\x00" to address for unix-abstract
-		addr.Addr = "\x00" + addr.Addr
+		// We can not prepend \0 as c++ gRPC does, as in Golang '@' is used to signify we do
+		// not want trailing \0 in address.
+		addr.Addr = "@" + addr.Addr
 	}
 	cc.UpdateState(resolver.State{Addresses: []resolver.Address{networktype.Set(addr, "unix")}})
 	return &nopResolver{}, nil