Fix ratio error

Author: mdboom

Tools/scripts/summarize_stats.py

@@ -419,8 +419,6 @@ def __init__(self, num: int, den: int | None, percentage: bool = True):
         self.num = num
         self.den = den
         self.percentage = percentage
-        if den == 0 and num != 0:
-            raise ValueError("Invalid denominator")
 
     def __float__(self):
         if self.den == 0: