test(litellm): Replace mocks with httpx types in nonstreaming completion() tests

[alexander-alderman-webb]

Description

Replace mocks with httpx types to avoid test failures when library internals change.

Issues

Reminders

• Please add tests to validate your changes, and lint your code using tox -e linters.
• Add GH Issue ID & Linear ID (if applicable)
• PR title should use conventional commit style (feat:, fix:, ref:, meta:)
• For external contributors: CONTRIBUTING.md, Sentry SDK development docs, Discord community

[github-actions]

Semver Impact of This PR

🟢 Patch (bug fixes)

📋 Changelog Preview

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Entries from this PR are highlighted with a left border (blockquote style).

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New Features ✨

• (ai) Redact base64 data URLs in image_url content blocks by ericapisani in #5953
• (integrations) Instrument pyreqwest tracing by servusdei2018 in #5682

Bug Fixes 🐛

Anthropic

• Capture exceptions for stream() calls by alexander-alderman-webb in #5950
• Stop setting transaction status when child span fails by alexander-alderman-webb in #5717
• Only finish relevant spans in .create() patches by alexander-alderman-webb in #5716

Other

• (litellm) Avoid double span exits when streaming by alexander-alderman-webb in #5933
• (pydantic-ai) Use first-class hooks when available by alexander-alderman-webb in #5947
• (wsgi) Respect HTTP_X_FORWARDED_PROTO in request.url construction by sl0thentr0py in #5963

Internal Changes 🔧

• (ai) Remove gen_ai.tool.type span attribute by ericapisani in #5964
• (anthropic) Separate sync and async .create() patches by alexander-alderman-webb in #5715

• (litellm) Replace mocks with httpx types in nonstreaming completion() tests by alexander-alderman-webb in #5937

• (openai) Split token counting by API for easier deprecation by ericapisani in #5930
• (opentelemetry) Ignore mypy error by alexander-alderman-webb in #5927
• Fix license metadata in setup.py by sl0thentr0py in #5934
• Update validate-pr workflow by stephanie-anderson in #5931

Other

• Handle None span context in the span processor and pin tokenizers version for anthropic tests on Python 3.8 by alexander-alderman-webb in #5967

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[github-actions]

Codecov Results 📊

✅ 79 passed | Total: 79 | Pass Rate: 100% | Execution Time: 939ms

All tests are passing successfully.

✅ Patch coverage is 100.00%. Project has 15782 uncovered lines.

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Generated by Codecov Action

[ericapisani]

LGTM