"Package would be ignored"

While building the conda-forge package of the MNE development version, I just saw dozens of messages like these in the log:

      ############################
      # Package would be ignored #
      ############################
      Python recognizes 'mne.report.js_and_css.highlightjs' as an importable package, however it is
      included in the distribution as "data".
      This behavior is likely to change in future versions of setuptools (and
      therefore is considered deprecated).

      Please make sure that 'mne.report.js_and_css.highlightjs' is included as a package by using
      setuptools' `packages` configuration field or the proper discovery methods
      (for example by using `find_namespace_packages(...)`/`find_namespace:`
      instead of `find_packages(...)`/`find:`).

      You can read more about "package discovery" and "data files" on setuptools
      documentation page.

Is this something we need to worry about?

Start by inspecting the packaging configuration and how the mne.report.js_and_css.highlightjs package is discovered and included. Reproduce the conda-forge build warning, then verify whether the package is included correctly without deprecated setuptools behavior.