outdated references in SDM tutorial

[plantarum]

The text in 2_sdm_occdata.rmd still references wrld_simpl in three places, but the code has been updated to use geodata::world.

rspatial-terra-web/source/sdm/_R/2_sdm_occdata.rmd

Line 159 in 33a26aa

Object 'ovr' has, for each point, the matching record from `wrld`. We need the variable 'NAME_0' in the data.frame of wrld_simpl

You also have one reference to gridSample, but don't mention dismo anymore. I think this is also an outdated line:

https://github.com/rspatial/rspatial-terra-web/blob/33a26aa24527e7e61114ccdb2e949173f659d640/source/sdm/_R/2_sdm_occdata.rmd#L240C44-L240C44

Thanks for maintaining this great resource!

[rhijmans]

And one more time, thank you very much!