fix(python): Update default of max_value_length (#14508)

We raised the default in https://github.com/getsentry/sentry-python/releases/tag/2.34.0, updating here.

Author: sentrivana

docs/platforms/python/configuration/options.mdx

@@ -172,14 +172,11 @@ Please note that the Sentry server [limits HTTP request body size](https://devel
 
 </SdkOption>
 
-<SdkOption name="max_value_length" type='int' defaultValue='1024'>
+<SdkOption name="max_value_length" type='int' defaultValue='100 000'>
 
 The number of characters after which the values containing text in the event payload will be truncated.
 
-<Alert level='warning'>
-  If the value you set for this is exceptionally large, the event may exceed 1
-  MiB and will be dropped by Sentry.
-</Alert>
+In SDK versions prior to 2.34.0, the default was 1024.
 
 </SdkOption>