feat: add load_extensions method

[maksims8]

Pull Request Type

• Feature addition
• Bugfix
• Documentation update
• Code refactor
• Tests improvement
• CI/CD pipeline enhancement
• Other: [Replace with a description]

Description

This commit introduces a new method in which you can overcome manually loading extensions you have in your project down to just one line and therefore allows your project setup time and complexity to be decreased.

Changes

• Introduces a new method to load extensions without manually looping and loading.

Test Scenarios

Non-recursive (loaded exts.example):

import interactions

intents = interactions.Intents.DEFAULT | interactions.Intents.MESSAGE_CONTENT
client = interactions.Client(intents=intents)

@interactions.listen()
async def on_ready():
    print("Client is ready.")

client.load_extensions("exts") # Folder is located in the root of the project
client.start("TOKEN")

Recursive (loaded exts.example & exts.subdir.example_two):

import interactions

intents = interactions.Intents.DEFAULT | interactions.Intents.MESSAGE_CONTENT
client = interactions.Client(intents=intents)

@interactions.listen()
async def on_ready():
    print("Client is ready.")

client.load_extensions("exts", recursive=True) # Folder is located in the root of the project
client.start("TOKEN")

Python Compatibility

• I've ensured my code works on Python 3.10.x
• I've ensured my code works on Python 3.11.x

Checklist

• I've run the pre-commit code linter over all edited files
• I've tested my changes on supported Python versions
• I've added tests for my code, if applicable
• I've updated / added documentation, where applicable

[silasary]

Other than a stray print() statement, this looks really good