Improve Documentation for Redis Setup

[wellcomemayhem-spec]

Issue: Improve Documentation for Redis Setup

The current setup instructions for installing and configuring Redis do not provide details on how to verify that Redis is running correctly before using djhtmx. This could lead to confusion among new users who may not be familiar with Redis.

Suggested Improvements:

1. Add a Verification Step: Include a step to check if Redis is running. For example, instruct users to run redis-cli ping to ensure Redis is up and responding with PONG.
2. Troubleshooting Section: Add a small section on common Redis issues or errors that users may encounter while setting it up or during initial usage with djhtmx.
3. Link to More Resources: Provide links to the official Redis documentation or tutorials for users who may need more in-depth installation instructions based on their operating system.

By enhancing the documentation with these suggestions, users will likely have a smoother onboarding experience with djhtmx.