Prior to this commit, ObjectToObjectConverter considered the return
type of non-static `to[targetType.simpleName]()` methods but did not
consider the return type of static `valueOf(sourceType)`,
`of(sourceType)`, and `from(sourceType)` methods.
This led to scenarios in which `canConvert()` returned `true`, but a
subsequent `convert()` invocation resulted in a
ConverterNotFoundException, which violates the contract of the
converter.
This commit addresses this issue by taking into account the return type
of a static valueOf/of/from factory method when determining if the
ObjectToObjectConverter supports a particular conversion. Whereas the
existing check in `determineToMethod()` ensures that the method return
type is assignable to the `targetType`, the new check in
`determineFactoryMethod()` leniently ensures that the method return
type and `targetType` are "related" (i.e., reside in the same type
hierarchy).
Closes gh-28609
452f1b877c