chore: Fix broken integrations tests

[jonathanedey]

• Replaces broken test links with a fake local server.
• Removes ReadTimeout integration tests as these are difficult to simulate with a mock server.

[gemini-code-assist]

Code Review

This pull request updates the external service URLs used in integration tests from nghttp2.org to httpbin.org. Feedback suggests replacing these external dependencies with a local mock server to improve test reliability and ensure the tests are hermetic.

[jonathanedey]

/gemini review

[gemini-code-assist]

Code Review

This pull request refactors the integration tests for ApacheHttp2Transport by replacing external network dependencies with a local FakeServer implementation. This change improves test reliability and execution speed. However, the review feedback identifies a likely copy-paste error in the read timeout tests, where the assertions incorrectly expect a 'Connection Timeout' message instead of a 'Read Timeout' message.

[jonathanedey]

/gemini review

[gemini-code-assist]

Code Review

This pull request refactors the ApacheHttp2TransportIT integration tests to use a local FakeServer instead of external endpoints, improving test reliability. The feedback suggests simplifying the FakeServer constructor using the ServerBootstrap builder and utilizing the close() method for more idiomatic resource management.