Add "/history" in magic_commands.py

[ayushmorbar]

Current behavior

• Currently, the program supports three commands: "/reset" and "/exit". The "/reset" command resets the chat session, and the "/exit" command shuts down the program. If an unrecognized command is entered, the program prints an error message.

Proposed changes

• The proposed changes include the addition of a new command "/history". This command, when invoked, prints out the chat history for the current session between NeoGPT and the user.

Checks

• The checks in this code are primarily conditional checks to determine which command the user has entered. If the user enters "/reset", the chat session is reset. If "/exit" is entered, the program shuts down. If "/history" is entered, the chat history is printed. If none of these commands are entered, an error message is printed.
• Ensured compatibility with existing file types.
• The code follows the project's coding style guidelines.
• Solved #137 Issue

• [x] All commits in this Pull Request are signed and Verified by Github.