Duplicate ModelConverter registration with Spring Boot DevTools

[SamuelGuillemet]

Hello,

I've recently encountered a new bug.

Issue Description:

Describe the bug
A newly created ModelConverter is being registered in duplicate when used with Spring Boot DevTools, due to the class loader being different.

To Reproduce
Steps to reproduce the behavior:

1. Create a Spring Boot application and include Spring Boot DevTools.
2. Add a new ModelConverter and annotate it with @Component

@Component
public final class OwnConverter implements ModelConverter {

    @Override
    public Schema resolve(AnnotatedType type, ModelConverterContext context, Iterator<ModelConverter> chain) {
        return (chain.hasNext()) ? chain.next().resolve(type, context, chain) : null;
    }
}

Expected behavior
The ModelConverter should be registered only once but every time the devtool restart the app, a new OwnConverter is added to the list of converters.

Additional context
I think the issue might comes from the following line where the comparaison is done through reference equality.
ModelConverterRegistrar.java#L102