DESCRIPTION: drop packages from Imports that aren't used in R/

[kyleam]

The 'R CMD check' for mpn.scorecard has the following note [*]:

Namespaces in Imports field not imported from:
   ‘here’ ‘markdown’ ‘tidyr’
  All declared Imports should be used.

here is only used in the top-level update-readme.R, not in any R/ code, so move it to pkgr.yml.

tidyr is only used in test code, so move it to Suggests.

markdown isn't used at all, so just remove it.

[*] This isn't flagged by the default devtools::check() (which
passes --as-cran) until R 4.2 (see revision 81155).

[barrettk]

Makes sense.

I will say markdown is a weird one though. Sometimes (even when I have rmarkdown installed), I will get a pop-up when trying to create a new RMD file saying

"Warning: a later version of markdown is required"

.. or something to that effect.

It may make sense to move markdown to just the pkgr file at some point, but R CMD Check / devtools::test() passes on my end so im good with how it is.

[kyleam]

I will say markdown is a weird one though. [...]

Okay, thanks for filling in those details. I like your plan of waiting to see if it crops up and then adding to pkgr.yml.