update junkdrawer.clamp type annotations

hypothesis-python/src/hypothesis/internal/conjecture/junkdrawer.py

@@ -243,7 +243,7 @@ def __check_index(self, i: int) -> int:
         return i
 
 
-def clamp(lower: int, value: int, upper: int) -> int:
+def clamp(lower: float, value: float, upper: float) -> float:
     """Given a value and lower/upper bounds, 'clamp' the value so that
     it satisfies lower <= value <= upper."""
     return max(lower, min(value, upper))