Refactor - Slack Service

[AntonyBishop]

User Need

As a Operations Engineering Team
I want to refactor bin items
so that we keep our code health, fit for purpose, and allow us to remove code that is no longer valid.

Value

Health code, reduces complexity, maintains level of awareness of code across the team.

Functional Requirements:

1. Script reviewed against team coding standards as well as any code references.
2. Any missing test code added.

Acceptance Criteria:

1. Necessary code changes made.
2. Tested and works as expected.