Button styling is off for column titles and pagination

The column titles appear as buttons with elevation when no style overrides are applied.

## Expected Behavior
The expected behavior is for the unmodified table to look like the images in the github repo

## Current Behavior
Notice the larger buttons on the icons and pagination as well as the elevation on the column titles.

## Steps to Reproduce (for bugs)
1. Install MUI data table
2. Implement with basic data

## Your Environment
I have run a fresh `npm install` with the following packages.

Package.json:
```json
"dependencies": {
"@emotion/react": "^11.10.6",
"@emotion/styled": "^11.10.6",
"@mui/icons-material": "^5.11.11",
"@mui/material": "^5.11.11",
"@mui/styles": "^5.9.3",
"@paypal/react-paypal-js": "^7.8.3",
"@testing-library/jest-dom": "^5.16.5",
"@testing-library/react": "^13.4.0",
"@testing-library/user-event": "^13.5.0",
"eslint-config-prettier": "^6.11.0",
"eslint-plugin-import": "^2.23.2",
"eslint-plugin-jest": "^24.3.6",
"eslint-plugin-prettier": "^3.1.4",
"fast-sort": "^3.2.1",
"ky": "^0.33.2",
"mui-datatables": "^4.3.0",
"prettier": "^2.2.1",
"react": "^18.2.0",
"react-dom": "^18.2.0",
"react-faq-component": "^1.3.4",
"react-pdf": "5.7.2",
"react-responsive": "^9.0.2",
"react-router-dom": "^5.2.1",
"react-scripts": "5.0.1",
"web-vitals": "^2.1.4",
"xlsx": "https://cdn.sheetjs.com/xlsx-0.18.12/xlsx-0.18.12.tgz"
}
```