Prior to this commit, if an appropriate Converter was registered with
the ConversionService that converts from a POJO to an array and that
ConversionService was registered with the Spring Expression Language
(SpEL) TypeConverter, an attempt to invoke a varargs method in a SpEL
expression with such a POJO would fail because the ConversionService
was not used to convert the POJO to an array suitable for the varargs
method invocation.
This commit revises the implementations of convertArguments(...) and
convertAllMethodHandleArguments(...) in ReflectionHelper to support
such use cases.
Closes gh-34371
b07217ab67