Adding unit test for updateDisposition closes link on timeout

[ki1729]

Description

Related to the change in PR - #22036
Added a unit test that verifies that link is closed when updateDisposition call fails with a timeout.

All SDK Contribution checklist:

• The pull request does not introduce [breaking changes]
• CHANGELOG is updated for new features, bug fixes or other significant changes.
• I have read the contribution guidelines.

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Testing Guidelines

• Pull request includes test coverage for the included changes.

[azure-sdk]

API change check for com.azure:azure-messaging-servicebus

API changes are not detected in this pull request for com.azure:azure-messaging-servicebus