refactor(ios): remove all unnecessary autorelease pool

[wwwcg]

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[hippy-service]

Hi, @wwwcg. Thanks for your PR! 👏

🏷️ You can leave a comment in this PR with #help tag when you need help (e.g. some status checks run failed due to internal issue), admin team members will help asap.

[tencent-adm]

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