Edit syntax for externalizing peer dependencies

[marlo-longley]

@lutzhelm this was your solution, but I wanted to put it up here for the community to look at for our meeting tomorrow.
I needed to use this in combination with #4139

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 94.91%. Comparing base (48ca7e0) to head (a37b056).
Report is 4 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #4142   +/-   ##
=======================================
  Coverage   94.91%   94.91%           
=======================================
  Files         324      324           
  Lines       16147    16147           
  Branches     2533     2533           
=======================================
  Hits        15326    15326           
  Misses        816      816           
  Partials        5        5           

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[gerdesque]

I can confirm that the build in dist/mirador.es.js does not contain the 'Incompatible React versions' error. LGTM.

[lutzhelm]

BTW, this is what gets hit by the function for external. Notably no @emotion/styled:

@emotion/react
@mui/material
@mui/material/Accordion
@mui/material/AccordionDetails
@mui/material/AccordionSummary
@mui/material/Alert
@mui/material/AppBar
@mui/material/Autocomplete
@mui/material/Backdrop
@mui/material/Badge
@mui/material/Button
@mui/material/ButtonBase
@mui/material/Checkbox
@mui/material/Chip
@mui/material/CircularProgress
@mui/material/Collapse
@mui/material/colors
@mui/material/Dialog
@mui/material/DialogActions
@mui/material/DialogContent
@mui/material/DialogTitle
@mui/material/Divider
@mui/material/Drawer
@mui/material/Fab
@mui/material/FormControl
@mui/material/FormControlLabel
@mui/material/GlobalStyles
@mui/material/Grid
@mui/material/Grid2
@mui/material/IconButton
@mui/material/Input
@mui/material/InputAdornment
@mui/material/InputLabel
@mui/material/Link
@mui/material/List
@mui/material/ListItem
@mui/material/ListItemButton
@mui/material/ListItemIcon
@mui/material/ListItemText
@mui/material/ListSubheader
@mui/material/Menu
@mui/material/MenuItem
@mui/material/MenuList
@mui/material/Paper
@mui/material/Popover
@mui/material/Select
@mui/material/Skeleton
@mui/material/Slide
@mui/material/Slider
@mui/material/Snackbar
@mui/material/Stack
@mui/material/styles
@mui/material/SvgIcon
@mui/material/Tab
@mui/material/Tabs
@mui/material/TextField
@mui/material/Toolbar
@mui/material/Tooltip
@mui/material/Typography
@mui/material/useMediaQuery
@mui/material/utils
@mui/system
@mui/system/createStyled
@mui/system/RtlProvider
react
react-dom
react-dom/client
react-i18next
react/jsx-runtime