[Lake][OHCLV] Update OHCLV data_factory to use csv_data_writer

[idiom-bytes]

Motivation

OHLCV is still writing/reading from parquet.

We may instead want to use the CSVDataStore + PersistentDataStore to save/read from. But doing this right now is hard, OHLCV code is tightly-bound w/ saving/loading/etc.

DoD

• OHCLV Data Factory CSV/Saving/Querying code has been abstracted away and is using CSVDataStore + PersistentDataStore
• OHCLV Data Factory and DataStore logic have been separated
• OHCLV Data Factory is querying from PersistentDataStore
• OHCLV Data Factory tests are up-to-date and every test is passing

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### Update According to Trent's comment

• Change the IO methods to a function, in a new module cvsutil.py
• use them into the CSVDataStore class and make it cleaner and thinner

[idiom-bytes]

CSV Data Store had already been integrated into duckdb-integration PR although @trentmc has provided feedback on the PR.

Trent: I'm not sure if we're able to currently merge w/ these updates before implementing feedback or not. Please let us know so we can organize this update.

[trentmc]

Trent: I'm not sure if we're able to currently merge w/ these updates before implementing feedback or not. Please let us know so we can organize this update.

For reference, I had two comments in the PR. I just checked. On the second comment, Mustafa gave a good response and addressed my concerns. So I "resolved" that comment in the PR.

On the first comment, it's a small thing. Easier to simply follow the suggestion now, than try to track later.

For convenience, here it is👇

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Both csv and duckDB are persistent data stores.

This file is csv_data_store.py, good.

The module for duckDB should be renamed from persistent_data_store.py to duckdb_data_store.py. (Otherwise its scope overlaps with that of csv_data_store.py)

[idiom-bytes]

Thank you for the response @trentmc, i'm starting to look at these peripheral duckdb items to sign off.