[stable/redis-ha]: configurable service's labels

[xabufr]

What this PR does / why we need it:

We need to customize some services labels without modifying all resources, this PR add some options to do this.

Checklist

[Place an '[x]' (no spaces) in all applicable fields. Please remove unrelated fields.]

• [x] DCO signed
• [x] Chart Version bumped
• [x] Variables are documented in the README.md
• [x] Title of the PR starts with chart name (e.g. [stable/mychartname])