nan/inf issue with chi2 likelihood def

.gitignore

@@ -2,6 +2,7 @@
 __pycache__/
 *.py[cod]
 *$py.class
+.ruff_cache
 
 # C extensions
 *.so

yaff/common_likelihoods.py

@@ -65,6 +65,11 @@ def chi2_likelihood(data: fitting.DataPacket, model: np.ndarray):
 
         # Some count bins might be negative, or have zero error,
         # so use nan_to_num
-        return -np.nan_to_num((numerator / total_sq_err)[restriction]).sum()
+        return -np.nan_to_num(
+            (numerator / total_sq_err)[restriction],
+            nan=0,
+            neginf=0,
+            posinf=0
+        ).sum()
 
     return chi2_likelihood