fix: use default value for encode and decode

[anonrig]

The default value for encode and decode is utf-8. We don't need to explicitly define it.

[bbayles]

Hmm, I think this is premature / potentially incorrect for exotic systems. PEP 686 will make UTF-8 mode the default in 3.15, but that's not out yet and we support older versions of Python. Since Python 3.7 UTF-8 mode is on for most users, but you're an environment variable away from having it off.

[TkTech]

@bbayles That's only for the internals. encode/decode do indeed explicitly default to utf-8 since at least 3.8, which is the lowest version allowed by the pyproject.toml:

 str.encode(encoding="utf-8", errors="strict")

    Return an encoded version of the string as a bytes object. Default encoding is 'utf-8'.

and:

 bytes.decode(encoding="utf-8", errors="strict")
bytearray.decode(encoding="utf-8", errors="strict")

    Return a string decoded from the given bytes. Default encoding is 'utf-8'.

[bbayles]

I stand corrected, thanks.