devservices: add eval taskworker offset reset target

[JoshFerge]

Summary

• add make devservices-evals-reset-taskworker-offset for local seeded eval runs
• reset the local taskworker Kafka consumer group to latest after stopping taskbroker
• clear taskbroker's local inflight store and restart eval taskworkers/taskbroker that were running

While debugging slow evals it was noticed sometimes the queues can get backlogged from old runs. this command helps us reset the queues before kicking off a fresh eval run

Verification

• bash -n scripts/devservices/reset-evals-taskworker-offset.sh
• make -n devservices-evals-reset-taskworker-offset

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