chore(Apple): Update docs to use @import Sentry;

[brustolin]

DESCRIBE YOUR PR

As we move away from Objective-C and create more features in Swift, these new features will only be available for use in other Objective-C projects if the developer imports the Sentry module instead of the umbrella header.

So I changed the Objective-c code snippets to reflect this.

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SLA

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  Thanks in advance for your help!

PRE-MERGE CHECKLIST

Make sure you've checked the following before merging your changes:

• Checked Vercel preview for correctness, including links
• PR was reviewed and approved by any necessary SMEs (subject matter experts)
• PR was reviewed and approved by a member of the Sentry docs team

[vercel]

The latest updates on your projects. Learn more about Vercel for Git ↗︎

Name	Status	Preview	Comments	Updated (UTC)
changelog	✅ Ready (Inspect)	Visit Preview	💬 Add feedback	Aug 6, 2024 2:27pm
sentry-docs	✅ Ready (Inspect)	Visit Preview	💬 Add feedback	Aug 6, 2024 2:27pm

1 Skipped Deployment

Name	Status	Preview	Comments	Updated (UTC)
develop-docs	⬜️ Ignored (Inspect)			Aug 6, 2024 2:27pm

[codecov]

Bundle Report

Changes will decrease total bundle size by 15 bytes ⬇️

Bundle name	Size	Change
sentry-docs-server	8.25MB	6 bytes ⬇️
sentry-docs-edge-server	252.6kB	3 bytes ⬇️
sentry-docs-client	6.24MB	6 bytes ⬇️

[krystofwoldrich]

LGTM 🚀