Various last-minute fixes

[pdiakumis]

• We can use CNAqc::example_dataset_CNAqc to load the example dataset

❯ checking R code for possible problems ... NOTE
  make_cnaqc_object: no visible global function definition for ‘data’
  make_cnaqc_object: no visible binding for global variable
    ‘example_dataset_CNAqc’
  Undefined global functions or variables:
    data example_dataset_CNAqc
  Consider adding
    importFrom("utils", "data")
  to your NAMESPACE file.

• Installing {openxlsx2} via the new conda setup
• Exporting strip_html
• Adding {caret} to the dependencies