[rollout] fix: remove code responsible for tool response duplication

[mgilmore-relace]

What does this PR do?

The _handle_processing_tools_state added the same tool response twice when using interactions. See here and here.

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[gemini-code-assist]

Code Review

This pull request aims to fix tool response duplication by removing a redundant code block. While this change is a step in the right direction and fixes one source of duplication when interactions are enabled, a more critical bug that also causes duplication remains in the _handle_processing_tools_state function.

The line agent_data.messages.extend(add_messages) at line 294 is incorrectly placed inside the for tool_response in responses: loop. This causes an incorrect number of messages to be added when multiple tools are called in a single turn. For N tool calls, it adds N*(N+1)/2 messages instead of N, with earlier messages being duplicated.

For example, with two tool calls, the messages list will be extended first with [message1] and then with [message1, message2], resulting in message1 being added twice.

The correct fix would be to move agent_data.messages.extend(add_messages) to after the loop finishes. I am pointing this out in this general summary as the affected line is outside the scope of the current changes. Given the severity, I strongly recommend addressing this in a follow-up PR. The current change is fine to merge as it does reduce some redundancy, but the core duplication issue for multiple tool calls persists.