[stable/redis-ha] add sentinel announce-hosts and resolve-hosts

[Alex-Souslik]

What this PR does / why we need it:

• add sentinel announce-hosts and sentinel resolve-hosts enabling values.
• use hostnames instead of IPs when these values are enabled.
• streamline sentinel.conf indentation.

Which issue this PR fixes

(optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close that issue when PR gets merged)

• fixes [chart/redis-ha][REQUEST] Redis Sentinel with TLS: go-redis fails host verification because Sentinel advertises IPs (no IP SANs) #354

Special notes for your reviewer:

Checklist

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

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

[devopsmash]

Hi @DandyDeveloper
Would you mind taking a look at this PR?

[devopsmash]

Hi @DandyDeveloper Is there anything else you need to move this PR forward?