[stable/redis-ha] Update network policy to allow HAProxy connectivity when enabled

[sean-mcgimpsey]

What this PR does / why we need it:

Allows connectivity from HAProxy pods to redis pods on 26379 6379 tcp when HAProxy is enabled

Which issue this PR fixes

155

Checklist

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• [/ ] Chart Version bumped
• [/ ] Title of the PR starts with chart name (e.g. [stable/mychartname])