fix tips bit

docs/Instruction/tips/register_bit.md

@@ -210,7 +210,7 @@ void loop() {
   delay(500);
   PORTA.OUT |= 0b00010000;  //Set PA4 to HIGH...(2)
   delay(500);
-  PORTA.OUT &= ~0b00000001; //Set PA0 to LOW....(3)
+  PORTA.OUT &= ~0b00000001; //Set PA0 to LOW ( Remaining PA4 setting )....(3)
 }
 ```
 ### What to work in (1)(2)(3)