minor #10807 [Validator] Range constraint: min and mix can be integer or string (wuestkamp)

This PR was squashed before being merged into the 3.4 branch (closes #10807).

Discussion
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[Validator] Range constraint: min and mix can be integer or string

When using this with `DateTime` the min and max can be strings.

Commits
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560a96f [Validator] Range constraint: min and mix can be integer or string

Author: xabbuh

reference/constraints/Range.rst

@@ -1,7 +1,7 @@
 Range
 =====
 
-Validates that a given number is *between* some minimum and maximum number.
+Validates that a given number or ``DateTime`` object is *between* some minimum and maximum.
 
 +----------------+---------------------------------------------------------------------+
 | Applies to     | :ref:`property or method <validation-property-target>`              |
@@ -320,15 +320,15 @@ Options
 min
 ~~~
 
-**type**: ``integer``
+**type**: ``int`` or ``string`` (date format)
 
 This required option is the "min" value. Validation will fail if the given
 value is **less** than this min value.
 
 max
 ~~~
 
-**type**: ``integer``
+**type**: ``int`` or ``string`` (date format)
 
 This required option is the "max" value. Validation will fail if the given
 value is **greater** than this max value.