Fix links and update Redis version support

[uglide]

No description provided.

[Copilot]

Pull Request Overview

This PR updates links and documentation to reflect current Redis resources and version support. The changes modernize the documentation by updating URLs from legacy domains to the current redis.io domain structure and expanding Redis version compatibility.

• Updates multiple Redis-related URLs from old domains (university.redis.com, redis.com) to current redis.io structure
• Expands supported Redis versions from 6.2-7.2 to 7.2-8.2
• Simplifies Docker command to use standard Redis image instead of Redis Stack

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