Mount only password of sharedState redis instance in KAS deployments

What does this MR do?

Mount only password of sharedState redis instance in KAS deployments as that is the only one required.

Testing

With the following config

redis:
  install: false
global:
  redis:
    host: redis.example
    port: 6379
    cache:
      host: cache.redis.example
      port: 6379
      auth:
        enabled: true
        secret: cache-secret
        key: cache-password
    sharedState:
      host: shared.redis.example
      port: 6379
      auth:
        enabled: true
        secret: shared-secret
        key: shared-password
    redisYmlOverride:
      chat:
        password:
          enabled: true
          secret: chat-secret
          key: chat-password

1. KAS pod should mount only redis/sharedState-password and the default redis/redis-password. cache and chat are omitted.
2. Sidekiq/Webservice/Toolbox pods should mount all Redis secrets - redis/cache-password, redis/sharedState-password, redis/chat-override-password, and the default redis/redis-password

Related issues

Closes #3847 (closed)

Checklist

See Definition of done.

For anything in this list which will not be completed, please provide a reason in the MR discussion.

Required

• Merge Request Title and Description are up to date, accurate, and descriptive
• MR targeting the appropriate branch
• MR has a green pipeline on GitLab.com
• When ready for review, MR is labeled "~workflow::ready for review" per the Distribution MR workflow

Expected (please provide an explanation if not completing)

• Test plan indicating conditions for success has been posted and passes
• Documentation created/updated
• Tests added
• Integration tests added to GitLab QA
• Equivalent MR/issue for omnibus-gitlab opened
• Validate potential values for new configuration settings. Formats such as integer 10, duration 10s, URI scheme://user:passwd@host:port may require quotation or other special handling when rendered in a template and written to a configuration file.