Remove broken function Layer.copy

This function has thrown an IndexError on the parameters
since 45e1c38 (7 years ago as of this
commit). We have not gotten a bug report of this. We can therefore be pretty sure nobody is using it.
In order to work properly, the call to _copy should not have the first argument layer.

python/resdata/grid/faults/layer.py

@@ -10,7 +10,6 @@
 class Layer(BaseCClass):
     TYPE_NAME = "rd_layer"
     _alloc = ResdataPrototype("void* layer_alloc(int,  int)", bind=False)
-    _copy = ResdataPrototype("void layer_memcpy(rd_layer, rd_layer)")
     _free = ResdataPrototype("void layer_free(rd_layer)")
     _get_nx = ResdataPrototype("int layer_get_nx(rd_layer)")
     _get_ny = ResdataPrototype("int layer_get_ny(rd_layer)")
@@ -54,12 +53,6 @@ def __init__(self, nx, ny):
         else:
             raise ValueError("Invalid input - no Layer object created")
 
-    @classmethod
-    def copy(cls, src):
-        layer = Layer(src.getNX(), src.getNY())
-        layer._copy(src)
-        return layer
-
     def _assert_ij(self, i, j):
         if i < 0 or i >= self.getNX():
             raise ValueError("Invalid layer i:%d" % i)

python/tests/rd_tests/test_layer.py

@@ -18,12 +18,6 @@ def test_create_layer(self):
         layer = Layer(10, 10)
         self.assertTrue(isinstance(layer, Layer))
 
-    def test_layer_copy(self):
-        layer = Layer(10, 10)
-        layer_copy = Layer.copy(layer)
-        assert layer.get_nx() == layer_copy.get_nx()
-        assert layer.get_ny() == layer_copy.get_ny()
-
     def test_add_cell(self):
         layer = Layer(10, 10)
         with self.assertRaises(ValueError):