[Bug]: `{openairmaps}` attempts to save file paths with illegal characters

[jack-davison-ricardo]

openairmaps::polar_data |>
  dplyr::mutate(cat = "<b>Category</b>") |>
  openairmaps::polarMap("pm10", control = "cat")
#> ℹ Assuming latitude is 'lat'
#> ℹ Assuming longitude is 'lon'
#> Error in `pmap()`:
#> ℹ In index: 1.
#> Caused by error in `grid.newpage()`:
#> ! could not open file 'C:\Users\JD38\AppData\Local\Temp\Rtmp2hiiVy/51.52229_-0.125889_<b>Category</b>_20240408123341.876413.png'
#> Backtrace:
#>      ▆
#>   1. ├─openairmaps::polarMap(...)
#>   2. │ └─openairmaps:::create_polar_markers(...)
#>   3. │   └─purrr::pwalk(...)
#>   4. │     └─purrr::pmap(.l, .f, ..., .progress = .progress)
#>   5. │       └─purrr:::pmap_("list", .l, .f, ..., .progress = .progress)
#>   6. │         ├─purrr:::with_indexed_errors(...)
#>   7. │         │ └─base::withCallingHandlers(...)
#>   8. │         ├─purrr:::call_with_cleanup(...)
#>   9. │         └─openairmaps (local) .f(...)
#>  10. │           ├─base::plot(..4)
#>  11. │           └─lattice:::plot.trellis(..4)
#>  12. │             └─grid::grid.newpage()
#>  13. └─base::.handleSimpleError(...)
#>  14.   └─purrr (local) h(simpleError(msg, call))
#>  15.     └─cli::cli_abort(...)
#>  16.       └─rlang::abort(...)

^{Created on 2024-04-08 with reprex v2.0.2}