Improve adding @Suppress at super class

[paul-dingemans]

Given code below:

@ExperimentalSerializationApi
public abstract class AbstractDecoder : Decoder, CompositeDecoder {
}

Supressing the class-signature rule on CompositeDecoder with ktlint-intellij-plugin leads to code like:

@ExperimentalSerializationApi
public abstract class AbstractDecoder : Decoder, @Suppress("ktlint:standard:class-signature")
CompositeDecoder {

It resolves the problem for CompositeDecoder but not for Decoder. The suppression annotation should be at the class instead:

@ExperimentalSerializationApi
@Suppress("ktlint:standard:class-signature")
public abstract class AbstractDecoder : Decoder, CompositeDecoder {