Issue importing Dataset class when using strands_evals package in evaluations samples.

[tech4life87]

Dataset class is no longer supported in favor of experiments class. Fix 04-trajectory-evaluation with the new experiments class.

[tech4life87]

https://github.com/strands-agents/samples/blob/main/07-evals/04-trajectory-evaluation/04-trajectory-evaluation.ipynb

I will create a pull request

[tech4life87]

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ImportError Traceback (most recent call last)
Cell In[2], line 9
6 from strands.multiagent import GraphBuilder
8 # Strands Evals imports
----> 9 from strands_evals import Dataset, Case
10 from strands_evals.evaluators import TrajectoryEvaluator
12 # Display utilities

ImportError: cannot import name 'Dataset' from 'strands_evals' (/Users/**/.pyenv/versions/3.12.5/envs/global/lib/python3.12/site-packages/strands_evals/init.py)