Change de_DE to de. de is the one that is active

Closes #3848 for PostGIS 3.0.0

git-svn-id: http://svn.osgeo.org/postgis/trunk@17312 b70326c6-7e19-0410-871a-916f4a2858ee
1 job for svn-trunk in 22 minutes and 28 seconds
Status Job ID Name Coverage
  Test
passed #174540923
test

00:22:28