fix(utils): Truncate aggregate exception values (LinkedErrors)

[Lms24]

As reported in #8580, aggregate exceptions' exception.value strings weren't truncated correctly in our event preparation pipeline. The tricky part here is that the LinkedErrors integration adds the linked/child exceptions to the event in an event processor which is applied only after we truncate the original event. Hence, we need to also truncate the values in the event processor itself.

closes #8580

[github-actions]

size-limit report 📦

Path	Size
@sentry/browser - ES5 CDN Bundle (gzipped + minified)	21.99 KB (+0.18% 🔺)
@sentry/browser - ES5 CDN Bundle (minified)	69.25 KB (+0.19% 🔺)
@sentry/browser - ES6 CDN Bundle (gzipped + minified)	20.33 KB (+0.23% 🔺)
@sentry/browser - ES6 CDN Bundle (minified)	60.48 KB (+0.17% 🔺)
@sentry/browser - Webpack (gzipped + minified)	21.95 KB (+0.21% 🔺)
@sentry/browser - Webpack (minified)	71.63 KB (+0.16% 🔺)
@sentry/react - Webpack (gzipped + minified)	21.96 KB (+0.19% 🔺)
@sentry/nextjs Client - Webpack (gzipped + minified)	50.83 KB (+0.14% 🔺)
@sentry/browser + @sentry/tracing - ES5 CDN Bundle (gzipped + minified)	30.37 KB (+0.15% 🔺)
@sentry/browser + @sentry/tracing - ES6 CDN Bundle (gzipped + minified)	28.25 KB (+0.18% 🔺)
@sentry/replay ES6 CDN Bundle (gzipped + minified)	49.44 KB (-0.01% 🔽)
@sentry/replay - Webpack (gzipped + minified)	43.16 KB (0%)
@sentry/browser + @sentry/tracing + @sentry/replay - ES6 CDN Bundle (gzipped + minified)	69.61 KB (+0.07% 🔺)
@sentry/browser + @sentry/replay - ES6 CDN Bundle (gzipped + minified)	61.88 KB (+0.08% 🔺)