SQL Server integration

[cyrannano]

Description

This PR introduces the integration of SQL Server support within the mindsql module. A new SQLServer class has been added, providing a comprehensive set of methods for connecting to and interacting with SQL Server databases. This includes executing SQL queries, retrieving database and table information, and obtaining DDLs for all tables in a specified database. Additionally, a suite of unit tests has been implemented to ensure the reliability and robustness of the SQL Server functionality.

Related Issue

N/A

Proposed Changes

• Added a new SQLServer class with methods for:
  • Creating a connection to SQL Server.
  • Executing SQL queries and returning results as pandas DataFrames.
  • Retrieving database and table information.
  • Validating SQL Server connections.
  • Retrieving DDLs for all tables in a specified database.
• Added unit tests for the SQLServer class to cover:
  • Connection creation (success and failure scenarios).
  • SQL query execution (success and failure scenarios).
  • Retrieval of databases and table names.
  • DDL retrieval for all tables and individual tables.
  • Connection validation.