r-exactextractr: package type fixed (#16881)

* r-exactextractr: should inherit from RPackage
* r-exactextractr: fixed URL

var/spack/repos/builtin/packages/r-exactextractr/package.py

@@ -6,15 +6,15 @@
 from spack import *
 
 
-class RExactextractr(AutotoolsPackage):
+class RExactextractr(RPackage):
     """Provides a replacement for the 'extract' function from the 'raster'
        package that is suitable for extracting raster values using 'sf'
        polygons.
     """
 
     homepage = "https://cloud.r-project.org/package=exactextractr"
-    url      = "https://cran.r-project.org/src/contrib/exactextractr_0.3.0.tar.gz"
-    list_url = "https://cran.r-project.org/src/contrib/Archive/exactextractr"
+    url      = "https://cloud.r-project.org/src/contrib/exactextractr_0.3.0.tar.gz"
+    list_url = "https://cloud.r-project.org/src/contrib/Archive/exactextractr"
 
     version('0.3.0', sha256='c7fb38b38b9dc8b3ca5b8f1f84f4ba3256efd331f2b4636b496d42689ffc3fb0')
     version('0.2.1', sha256='d0b998c77c3fd9265a600a0e08e9bf32a2490a06c19df0d0c0dea4b5c9ab5773')