Editor outputs incorrect string representation of `Bytes`

[tonyfettes]

Pick any of the editor on the documentation website here and modify the result as

fn main {
  let b1 : Bytes = b"abcd"
  println(b1) // true
}

It will output:

ac

while we expect it to output:

b"\x61\x62\x63\x64"

Reported by @Demonmasterlqx

[bobzhang]

note this bug only appears in the code mirror based IDE, I could not reproduce in https://try.moonbitlang.cn/

[peter-jerry-ye]

This is likely due to the out-of-dated moonbit-pad @bzy-debug