Fixed #34211 -- Optimized ForeignKey deferred attribute setting.

[Rusheel1306]

Trac ticket number

ticket-34211

Branch description

Provide a concise overview of the issue or rationale behind the proposed changes.
optimsed the code to run at half the time. brief explanation added.
AI used - Gemini 3 Pro.

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Checklist

• This PR follows the contribution guidelines.
• This PR does not disclose a security vulnerability (see vulnerability reporting).
• This PR targets the main branch.
• The commit message is written in past tense, mentions the ticket number, and ends with a period.
• I have checked the "Has patch" ticket flag in the Trac system.
• I have added or updated relevant tests.
• I have added or updated relevant docs, including release notes if applicable.
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[github-actions]

📊 Coverage Report for Changed Files

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Diff Coverage
Diff: origin/main...HEAD, staged and unstaged changes
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django/db/models/fields/related_descriptors.py (100%)
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Total:   7 lines
Missing: 0 lines
Coverage: 100%
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