Add Support for QA and Summarization Tasks for CSV Dataset

[Prikshit7766]

Description:
Currently, the Harness class supports text classification for CSV datasets. However, there is a need to extend its capabilities to include support for QA (Question Answering) and summarization tasks on CSV data. This enhancement will allow users to perform QA and summarization tasks using the Harness class with CSV datasets.

Example Usage:

harness = Harness(task="summarization", hub="openai", model="gpt-3.5-turbo",
                  data={
                      "name": r"news_summary_more.csv",
                      "feature_column": "headlines",
                      "target_column": "text"
                  })