Replace usages of whitelist/blacklist and master/slave

[letzya]

Branch/Environment/Version

All releases up to today (2.9.4.1)

Relevant Document

Describe the error

Replace usages of whitelist/blacklist and master/slave.
This probably needs a bit of research before changing the docs.

My personal choice, based on the term I practice on a daily basis:

1. Master/slave ==> Primary/worker
   Off docs, we already use:

• primary DC, primary redis, primary gw.
• worker DC, worker GW. Redis-secondary

2. Blacklist/white list ==> blocked list/allowed list or blocklist/allowlist

Screenshots/Video

Additional context

this doc can offer some options https://tools.ietf.org/id/draft-knodel-terminology-00.html#rfc.section.1.1

[marksou]

We could use Allow List and Deny List instead of White and Blacklist.

[joshblakeley]

While we're here change referring to master branches with main since that will change too

[davegarvey]

For the data centre stuff we could use data plane and control plane.