Docs: fix typos of 'whether' in operator_{gt,le,lt}.md (#4412)

docs/mkdocs/docs/api/basic_json/operator_le.md

@@ -17,7 +17,7 @@ bool operator<=(ScalarType lhs, const const_reference rhs) noexcept;  // (2)
       operand is `NaN` and the other operand is either `NaN` or any other number.
     - Otherwise, returns the result of `#!cpp !(rhs < lhs)` (see [**operator<**](operator_lt.md)).
 
-1. Compares wether a JSON value is less than or equal to a scalar or a scalar is less than or equal
+1. Compares whether a JSON value is less than or equal to a scalar or a scalar is less than or equal
    to a JSON value by converting the scalar to a JSON value and comparing both JSON values according
    to 1.