Update Cohort 7 Notebook with Data Loading from Warehouse and Code Cleanup

[hanlunBCRegistries]

Issue: #288

Description:

This PR introduces several updates to the Cohort 7 notebook, focusing on loading data from the warehouse, improving code structure, and cleaning up unnecessary outputs.

Key Changes:

• Data Loading:

  • Integrated logic to load business data from the Warehouse.
  • Created an updated get_pool() function for better connection pooling, enabling both Business and Warehouse database connections.

• Code Cleanup:

  • Removed all previous cell outputs for a cleaner notebook state.
  • Deleted obsolete CSV files.

• Data Processing Enhancements:

  • Updated SQL queries to pull business data from COLIN and process it for AR reminders.
  • Improved formatting of columns and handled data types for easier insertion into the Business AR database.

• General Improvements:

  • Streamlined environment variable loading for better clarity and reusability.
  • Fixed column name mappings and data conversions for smoother execution.