[Bug]: test after test_block_example test often hangs for Python 3.14 build

[SilanHe]

Expected Behavior

I expect these tests to pass 100% of the time.

Actual Behavior

Non deterministically, a test will hang and the Github Actions build will be blocked until the workflow times out.

See: https://github.com/aws/aws-durable-execution-sdk-python/actions/runs/26851761772/job/79186338754?pr=413#step:7:1195

Steps to Reproduce

1. Open pull request
2. run build workflow

I haven't personally experienced this locally.

SDK Version

latest on Github after 1.5.0

Python Version

3.14

Is this a regression?

n/a

Last Working Version

No response

Additional Context

No response

[zhongkechen]

Stuck in 3.13 as well, e.g.: https://github.com/aws/aws-durable-execution-sdk-python/actions/runs/26980408329/job/79617937398?pr=417

[zhongkechen]

Fixed in #498