write_summary_box_hep_summary: Write and style summary box in HEP summary sheet
In ElliottMess/rapporteur: Reports on triple billion data

write_summary_box_hep_summary writes and styles the summary box in HEP summary worksheet. Used in write_hep_summary_sheet().

write_summary_box_hep_summary(
  wb,
  sheet_name,
  iso,
  start_year,
  end_year,
  boxes_bounds
)

`wb`	a `openxlsx` workbook to be edited.
`sheet_name`	character name of the sheet to update
`iso`	ISO3 code of country to summarize.
`start_year`	Base year for contribution calculation, defaults to 2018.
`end_year`	End year(s) for contribution calculation, defaults to 2019 to 2025.
`boxes_bounds`	named list of bounds for data frame boxes to be written in sheet.