Allow some tolerance in test comparison (#219)

* Allow some tolerance in test comparison

Note that the default is relative tol = 1e-5 & absolute tol = 1e-8. I'm
also considering NaNs as equal values.

* Removing nan_equal

As suggested by @grantbuster since it was not supposed to have any NaN.

tests/forward_pass/test_forward_pass.py

@@ -173,8 +173,8 @@ def test_fwp_single_ts_vs_multi_ts_input_files():
 
  with xr.open_dataset(sf) as s_res, xr.open_dataset(mf) as m_res:
  for feat in model.meta['hr_out_features']:
- assert np.array_equal(s_res[feat].values,
-  m_res[feat].values)
+ assert np.allclose(s_res[feat].values,
+ m_res[feat].values)
 
 
 def test_fwp_spatial_only():