Many GDAL ENCODING warnings pop up for terra::spatVector() unit tests in Ubuntu

[florisvdh]

This can e.g. be seen in https://github.com/r-spatial/qgisprocess/actions/runs/7259352022/job/19776322636#step:22:45.

It was found that these warnings disappear if test-compat-raster.R is removed; this file is run before test-compat-terra.R, so an interplay between {raster} and {terra} is at stake.

This could be reduced to the following finding. On Ubuntu, it appears that if raster::raster() has been called, subsequently writing a SpatVector object to a GeoPackage with terra::writeVector() emits the warning.

Reported at https://github.com/rspatial/terra/issues/1377.