fixup! fixup! Add JavaDocs for PRF extension

Author: emlun

webauthn-server-core/src/main/java/com/yubico/webauthn/data/AssertionExtensionInputs.java

@@ -31,6 +31,7 @@
 import com.yubico.webauthn.StartAssertionOptions;
 import com.yubico.webauthn.extension.appid.AppId;
 import java.util.HashSet;
+import java.util.Map;
 import java.util.Optional;
 import java.util.Set;
 import lombok.Builder;