LibJS: Make get_option() options Object a const&

This only calls Object::get() on the options Object, which is
const-qualified.

Userland/Libraries/LibJS/Runtime/Temporal/AbstractOperations.cpp

@@ -103,7 +103,7 @@ Object* get_options_object(GlobalObject& global_object, Value options)
 }
 
 // 13.3 GetOption ( options, property, types, values, fallback ), https://tc39.es/proposal-temporal/#sec-getoption
-Value get_option(GlobalObject& global_object, Object& options, PropertyName const& property, Vector<OptionType> const& types, Vector<StringView> const& values, Value fallback)
+Value get_option(GlobalObject& global_object, Object const& options, PropertyName const& property, Vector<OptionType> const& types, Vector<StringView> const& values, Value fallback)
 {
     VERIFY(property.is_string());
 

Userland/Libraries/LibJS/Runtime/Temporal/AbstractOperations.h

@@ -85,7 +85,7 @@ struct SecondsStringPrecision {
 
 MarkedValueList iterable_to_list_of_type(GlobalObject&, Value items, Vector<OptionType> const& element_types);
 Object* get_options_object(GlobalObject&, Value options);
-Value get_option(GlobalObject&, Object& options, PropertyName const& property, Vector<OptionType> const& types, Vector<StringView> const& values, Value fallback);
+Value get_option(GlobalObject&, Object const& options, PropertyName const& property, Vector<OptionType> const& types, Vector<StringView> const& values, Value fallback);
 template<typename NumberType>
 Optional<Variant<String, NumberType>> get_string_or_number_option(GlobalObject&, Object& options, PropertyName const& property, Vector<StringView> const& string_values, NumberType minimum, NumberType maximum, Value fallback);
 Optional<String> to_temporal_overflow(GlobalObject&, Object& normalized_options);