ci: clarify Redis version in job name

[Tony133]

Proposal:

• Adds the word "Redis" to the job name in the test matrix.
• The GitHub Actions check list currently shows job names like Node.js 20 - 5 ( see screenshot ), which doesn't make clear that 5 refers to the Redis version being tested. This makes the checks harder to read at a glance, especially in the PR checks list.

Changes:

• Before: Node.js 20 - 5
• After: Node.js 20 - Redis 5

Note:

• Single line change in the workflow name: field, no functional impact.