Fix OSS fbthrift-python build failures

Summary:
1. Add missed closeable Extension and re-enable the thrift.python.streaming package in setup.py. The streaming package was disabled and the closeable.pyx Cython extension was never registered, which caused ModuleNotFoundError at import time.

2. Remove the unconditional enable_tests=ON from [cmake.defines.os=linux] in the fbthrift-python manifest. This override forced tests on during dependency builds even when --no-tests was passed, which triggered a find_package(benchmark) failure. Add benchmark as an explicit dependency so test builds resolve correctly.

3. Remove test_queue_timeout from client_server tests. The test is architecturally incompatible with thrift-python's async handler model: combinedHandler calls create_task() and returns instantly, so the C++ executor dequeues all requests and calls tryStartProcessing() before the 10ms queue timeout timer fires. No blocking in the Python handler can cause requests to sit in the C++ resource pool queue long enough for the timeout to trigger.

4. Fix test_flag_behavior_matrix for stdlib Flag on OSS Python 3.12. Python stdlib Flag.__contains__ does not support `0 in FlagType` on all Python 3.12 builds. Skip the 0-containment check for stdlib PyFlag subclasses — only test it for thrift-python Flag types.

5. Remove unused SocketAddress import from client_server.py (was only used by the deleted test_queue_timeout).

Reviewed By: vitaut

Differential Revision: D99921093

fbshipit-source-id: 82dd9f939b7617d0ed244088bea020178ee9f3ca

Author: Satish Kumar

build/fbcode_builder/manifests/fbthrift-python

@@ -28,9 +28,9 @@ enable_tests=OFF
 
 [cmake.defines.os=linux]
 thrift_python=ON
-enable_tests=ON
 
 [dependencies]
+benchmark
 fizz-python
 fmt-python
 folly-python