Add debug code for failing test on windows

Signed-off-by: Austin Vazquez <[email protected]>

client.go

@@ -19,6 +19,7 @@ package ttrpc
 import (
 	"context"
 	"errors"
+	"fmt"
 	"io"
 	"net"
 	"os"
@@ -105,7 +106,7 @@ type callRequest struct {
 func (c *Client) Call(ctx context.Context, service, method string, req, resp interface{}) error {
 	payload, err := c.codec.Marshal(req)
 	if err != nil {
-		return err
+		return fmt.Errorf("marshal error: %v", err)
 	}
 
 	var (
@@ -130,11 +131,11 @@ func (c *Client) Call(ctx context.Context, service, method string, req, resp int
 		FullMethod: fullPath(service, method),
 	}
 	if err := c.interceptor(ctx, creq, cresp, info, c.dispatch); err != nil {
-		return err
+		return fmt.Errorf("interceptor error: %v", err)
 	}
 
 	if err := c.codec.Unmarshal(cresp.Payload, resp); err != nil {
-		return err
+		return fmt.Errorf("unmarshal error: %v", err)
 	}
 
 	if cresp.Status != nil && cresp.Status.Code != int32(codes.OK) {