should use DictionaryArray::with_values instead of try_new on the dictionary fast path

[Rich-T-kid]

Is your feature request related to a problem or challenge? Please describe what you are trying to do.
In arrow-string/src/substring.rs:88-90 (inside the substring_dict! macro), the dictionary fast path rebuilds the result with DictionaryArray::try_new
Since the keys are unchanged and the values' length is unchanged (one substring per dictionary value), this is exactly what
https://docs.rs/arrow-array/latest/arrow_array/array/struct.DictionaryArray.html#method.with_values is for:

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Pretty small change, noticed it while working on REE but I dont want to clutter the PR

[alamb]

label_issue.py automatically added labels {'arrow'} from #9894