[Code]: Number literal constant is used, suggest using hex format

**Framework version:** v11
**Description**: U64 literal constant 18446744073709551615u64 is used in Bitwise.move. The decimal format is error-prone and difficult to recognize.
**Code Location:** sources/Bitwise.move, line 26
```
/// bit not: !x
public fun not(x: u64): u64 {
   (x ^ 18446744073709551615u64 as u64)
}
```