fix a slicing error where a -1 on the end-bound index was missing causing an occasional crash.

Author: KathleenLabrie

gempy/library/telluric.py

@@ -312,7 +312,7 @@ def make_stellar_mask(self, threshold=0.9, grow=1, max_contiguous=40,
             self.waves, mask=stellar_mask))
         stellar_mask = np.zeros_like(stellar_mask)
         for _slice in masked_slices:
-            if abs(self.waves[_slice.stop] -
+            if abs(self.waves[_slice.stop - 1] -
                    self.waves[_slice.start]) <= max_contiguous:
                 stellar_mask[_slice] = True
         if grow > 0: