Add has_bos to Jetstream decode request

[SurbhiJainUSC]

Description

This PR sets has_bos=True in JetStream decode request because generate_distillation_data.py applies chat template to the prompt before sending it to JetStream for decoding. Initially, JetStream was hardcoding bos token to all the prompts before running inference. This was corrupting our results for distillation. PR in JetStream fixes this issue and added a new argument to DecodeRequest proto.

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Tests

Tested by running generate_distillation_data.py

Checklist

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• I have performed a self-review of my code.
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