fix(google-genai): deactivate google genai when langchain is used

[shellmayr]

• we are seeing duplicate spans for google genai and langchain
• deactivate google genai when langchain is used

[github-actions]

Semver Impact of This PR

🟢 Patch (bug fixes)

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Bug Fixes 🐛

• fix(dramatiq): cleanup isolated scope and transaction when message is skipped by frankie567 in #5346

• fix(google-genai): deactivate google genai when langchain is used by shellmayr in #5389

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