Use "allow list" terminology instead of whitelist

Description

We should remove offending words from the code base (e.g. blacklist, whitelist).

See CASSANDRA-15862 for more info.

Environment

None
Fixed

Assignee

Unassigned

Reporter

Joao Reis

Labels

None

PM Priority

None

Fix versions

None

External issue ID

None

Doc Impact

None

Reviewer

None

Pull Request

None

Epic Link

None

Sprint

C# P-NEXT

Pull Requests

None

Size

None

Priority

Major