Support for protobuf 4.x

[vivekkothari]

Protobuf 4.x removed GeneratedMessageV3 class (grpc/grpc-java#11015), https://protobuf.dev/news/2023-12-05/

This is causing

public final class RequiredValidation {
    private RequiredValidation() {
    }

    public static void required(String field, GeneratedMessageV3 value) throws ValidationException {
        if (value == null) {
            throw new ValidationException(field, "null", "is required");
        }
    }
}

This class to break as its using GeneratedMessageV3, but my code no longer uses GeneratedMessageV3 but uses GeneratedMessage
Can we modify this to simply use Message interface? I didn't understand why we used GeneratedMessage*? AFAIK they are supposed to be internal protobuf classes which are not supposed to be used outside of protobuf code.

[vivekkothari]

When is the next planned release?