Fix the greeks calculations of the chain command

[northern-64bit]

Description

This makes the greeks calculations in the chains command (with YahooFinance) accurate. Closes #3779. There will still exist a difference between the sources due to different IV values, current asset prices (when the market is open) and so on ..., namely due to the data given.

How has this been tested?

Running the command and comparing results with Nasdaq, Tradier and the greeks command.

Checklist:

• Update our Hugo documentation following these guidelines.
• Update our tests following these guidelines.
• Make sure you are following our CONTRIBUTING guidelines.
• If a feature was added make sure to add it to the corresponding scripts file.

Others

• I have performed a self-review of my own code.
• I have commented my code, particularly in hard-to-understand areas.