Documents and Use sendDefaultPii=true in docs and in product getting started guide

[krystofwoldrich]

Description

• Umbrella issue Document and add sendDefaultPii: true to onboarding docs team-sdks#121 and Document data collected by SDKs team-sdks#82

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1. Java/Android Pii docs Document data collected by the SDKs sentry-java#4092
2. Cocoa Pii docs Apple: Document Data Collected sentry-docs#12751
3. JavaScript docs Document data collected by the SDKs sentry-java#4092

Tasks

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1. Add to RN docs (link native docs and javascript, note RN specifics)
2. Add to RN in product getting started
3. Add to sentry/wizard code snippet