[BUG] Broken MUI styles

[jurajpiar]

Describe the bug
When a component that uses MUI styles is added as a sibling to the RUI Footer some of the components' styles are being overwritten by MUI default styles.

To Reproduce
Steps to reproduce the behaviour:

1. Go to marketplace-ui repo
2. Checkout staging branch
3. Reset (hard) on commit 9391efe311842e13416c7767da0fe2ab2d1ecaa9
4. Run the application
5. The login button will have incorrect styling
6. The main title will have incorrect styling
7. Go to FAQ page
8. The title will have incorrect styling

Expected behaviour
A clear and concise description of what you expected to happen.

Screenshots

The effects of the bug have been captured in https://rsklabs.atlassian.net/browse/RMKT-512?focusedCommentId=19495 during QA review.