[Validator] Use correct single quotes for a string

Author: wkania

reference/constraints/IsFalse.rst

@@ -3,7 +3,7 @@ IsFalse
 
 Validates that a value is ``false``. Specifically, this checks to see if
 the value is exactly ``false``, exactly the integer ``0``, or exactly the
-string "``0``".
+string ``'0'``.
 
 Also see :doc:`IsTrue <IsTrue>`.
 

reference/constraints/IsTrue.rst

@@ -2,7 +2,7 @@ IsTrue
 ======
 
 Validates that a value is ``true``. Specifically, this checks if the value is
-exactly ``true``, exactly the integer ``1``, or exactly the string ``"1"``.
+exactly ``true``, exactly the integer ``1``, or exactly the string ``'1'``.
 
 Also see :doc:`IsFalse <IsFalse>`.