Max length in strip_string() should by bytes not characters.

[antonpirker]

How do you use Sentry?

Sentry Saas (sentry.io)

Version

1.9.10

Steps to Reproduce

If you use this function:
https://github.com/getsentry/sentry-python/blob/master/sentry_sdk/utils.py#L834-L854

If you use a value that contains unicode characters like this one:
Randolph Carter est obsédé par la redécouverte de la ville du coucher, la ville de ses rêves.

Expected Result

The truncation and indexes in the AnnotatedValue should be done by number of bytes and not number of characters.

Actual Result

The index range in the resulting AnnotatedValue is wrong, because it is the len() in characters and not the len in bytes.

To use the byte length one has to use something like this:

length = len(value.encode("utf-8"))