Improve DownloadData Extension to Deserialize to T

[Martin-Molinero]

Expected Behavior

• Being able to download and deserialize to T with helper method

Actual Behavior

• We download a string and later need to deserialize it to T. See https://github.com/QuantConnect/Lean.Brokerages.dYdX/blob/master/QuantConnect.dYdXBrokerage/dYdXBrokerage.cs#L440-L442

Potential Solution

Add new overload to deserialize to T, would be nice to also allow optionally providing json settings to use

Reproducing the Problem

httpClient.DownloadData(url)

System Information

N/A

Checklist

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