Missing vector clock update for Unfair BatchSemaphore release

No clock update here: https://github.com/awslabs/shuttle/blob/c8a46d3965048df3207ec920dae066bc9c4d9d89/shuttle-core/src/future/batch_semaphore.rs#L608-L612, but clock update here: https://github.com/awslabs/shuttle/blob/c8a46d3965048df3207ec920dae066bc9c4d9d89/shuttle-core/src/future/batch_semaphore.rs#L268-L274

Start in shuttle-core/src/future/batch_semaphore.rs, comparing the release code around lines 608-612 with the clock update around lines 268-274. Trace the Unfair BatchSemaphore release path and verify that its vector-clock behavior matches the referenced path; the relevant concurrency tests should pass when the issue is fixed.

Written by the indexing model from the issue text.