[skyrl-gym] search env cleanup

[erictang000]

What does this PR do

Cleans up _parse_action to just parse the action:

def _parse_action(self, action: str) -> List[Optional[str]]:
        match = None
        if "<search>" in action and "</search>" in action:
            match = re.search(r"<search>(.*?)</search>", action, re.DOTALL)
        return [match.group(1)] if match else [None]

since we are always using

tool_group_name = self.tool_group.get_name()
tool_name = self.tool_group.get_tool_names()[0]

[tyler-griggs]

Thanks! If you haven't already, could you just launch a training run for 1 step to sanity check that this all works?

[erictang000]

Thanks! If you haven't already, could you just launch a training run for 1 step to sanity check that this all works?

training is running!