[#301] rpc: Make client stream initialization get cancelled by dial timeout

* `c.conn` may be already invalidated but the rpc client can't detect this.
  `NewStream` may hang trying to open a stream with invalidated connection.
  Using timer with `dialTimeout` for `NewStream` fixes this problem.

Signed-off-by: Airat Arifullin <a.arifullin@yadro.com>

api/rpc/client/init.go

@@ -67,7 +67,7 @@ func (c *Client) Init(info common.CallMethodInfo, opts ...CallOption) (MessageRe
 		stream grpc.ClientStream
 		err    error
 	}
-	newStreamCh := make(chan newStreamRes, 1)
+	newStreamCh := make(chan newStreamRes)
 
 	go func() {
 		stream, err := c.conn.NewStream(ctx, &grpc.StreamDesc{