docs: use jump_url instead of content for getting started guide

[AstreaTSS]

Pull Request Type

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

Description

This PR changes up the Getting Started guide so that the example uses jump_url instead of content when showing off the message create event. This ensures the example always works as expected with the intents (the default ones) specified in said example.

Changes

its like a one line diff lol

Related Issues

Test Scenarios

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