Adds Janitor ERT Obj Icon (#6061)

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## About The Pull Request

1. **Adds Janitor ERT Obj Icon.**

## Why It's Good For The Game

1. _The Janitor ERT Hardsuit object icon is missing - or may not have
existed. Just whipped one together real quick._

## Changelog

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:cl:
add: Adds Janitor ERT Obj icon.
/:cl:

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