Added Bluesky and Slack icons

[sc-ivanlieckens]

Description / Motivation

Adds the missing icons for Slack and Bluesky.

Any profile links added of these types used the generic link icon.

How Has This Been Tested?

Manual UI Tests

Local Docker

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• I have read the Contributing guide.
• My code/comments/docs fully adhere to the Code of Conduct.
• My change is a code change.
• My change is a documentation change and there are NO other updates required.