Fix Medium icon which is hidden on Docusaurus footer

[znamazbayeva]

Description

The medium icon can not be seen because the icon only appeared in library starting from version 4.3.0. Therefore, I have updated the version of the library and added the medium icon.

The icon are similar except the instagram icon which was upgraded I guess.

Fixes #1148

Type of Change:

• Code

Code/Quality Assurance Only

• Bug fix (non-breaking change which fixes an issue)

How Has This Been Tested?

Checklist:

• My PR follows the style guidelines of this project
• I have performed a self-review of my own code or materials

Code/Quality Assurance Only

• My changes generate no new warnings

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[znamazbayeva]

Hello @isabelcosta! I think there is a problem with the test units as I have understood from #1153. What I can do with it? Can you check my solution?