@material-ui/core updates

[engelhartrueben]

Fixes # (issue)

1. Changes all mentions of import { createMuiTheme } to import { createTheme}
2. Change all mentions of rowsMax to maxRows
3. Change all mentions of rowsMin to minRows

Description

@material-ui/core update 4.11.3 => 4.12.4

Updates that affect Spoke come from the 4.12.0 update => https://github.com/mui/material-ui/blob/v4.12.0/CHANGELOG.md

Working gist: https://gist.github.com/engelhartrueben/0ed94c11a6cd5af27c0480d148492c66

Hard to test without working yarn dev; will need to be reviewed when able.

Checklist:

• [ ] I have manually tested my changes on desktop and mobile
• [ ] The test suite passes locally with my changes
• [x] If my change is a UI change, I have attached a screenshot to the description section of this pull request
• [x] My change is 300 lines of code or less, or has a documented reason in the description why it’s longer
• [x] I have made any necessary changes to the documentation
• [ ] I have added tests that prove my fix is effective or that my feature works
• [ ] My PR is labeled [WIP] if it is in progress

[engelhartrueben]

Good to go. No further commits needed.