Bump @mui/styles from 5.15.15 to 5.15.19

Bumps [@mui/styles](https://github.com/mui/material-ui/tree/HEAD/packages/mui-styles) from 5.15.15 to 5.15.19.
- [Release notes](https://github.com/mui/material-ui/releases)
- [Changelog](https://github.com/mui/material-ui/blob/v5.15.19/CHANGELOG.md)
- [Commits](https://github.com/mui/material-ui/commits/v5.15.19/packages/mui-styles)

---
updated-dependencies:
- dependency-name: "@mui/styles"
  dependency-type: direct:development
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

package.json

@@ -46,7 +46,7 @@
     "@iobroker/testing": "^4.1.3",
     "@mui/icons-material": "^5.15.15",
     "@mui/material": "^5.15.15",
-    "@mui/styles": "^5.15.15",
+    "@mui/styles": "^5.15.19",
     "@tsconfig/node16": "^16.1.3",
     "@types/chai": "^4.3.4",
     "@types/chai-as-promised": "^7.1.8",