swap begin/wait for esp32

examples/GPS_HardwareSerial_EchoTest/GPS_HardwareSerial_EchoTest.ino

@@ -20,12 +20,12 @@
 
 
 void setup() {
-  // wait for hardware serial to appear
-  while (!Serial);
-
   // make this baud rate fast enough to we aren't waiting on it
   Serial.begin(115200);
 
+  // wait for hardware serial to appear
+  while (!Serial) delay(10);
+
   // 9600 baud is the default rate for the Ultimate GPS
   GPSSerial.begin(9600);
 }