average resample method doesn't work when applied later in process graph

[jdries]

When resample_cube_spatial with average method is performed after an apply process (so not at load_collection time), the resamplemethod doesn't return the expected result.

When load_collection loads data from tiff, downsampling with non-default method also doesn't give expected result.

The cause is this Geotrellis issue:
locationtech/geotrellis#3541