[CHORE] Update GUI Frontend to v5.15.19

[renovate[bot]]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
@mui/icons-material (source)	5.15.18 -> 5.15.19
@mui/material (source)	5.15.18 -> 5.15.19

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Release Notes

mui/material-ui (@​mui/icons-material)

### [`v5.15.19`](https://togithub.com/mui/material-ui/compare/v5.15.18...v5.15.19) [Compare Source](https://togithub.com/mui/material-ui/compare/v5.15.18...v5.15.19)

mui/material-ui (@​mui/material)

### [`v5.15.19`](https://togithub.com/mui/material-ui/compare/v5.15.18...v5.15.19) [Compare Source](https://togithub.com/mui/material-ui/compare/v5.15.18...v5.15.19)

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Configuration

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