Add annotations to EventTemplateAdditionalField builder
diff --git a/log4j-layout-json-template/src/main/java/org/apache/logging/log4j/layout/json/template/JsonTemplateLayout.java b/log4j-layout-json-template/src/main/java/org/apache/logging/log4j/layout/json/template/JsonTemplateLayout.java
index a5118c2..3ef88af 100644
--- a/log4j-layout-json-template/src/main/java/org/apache/logging/log4j/layout/json/template/JsonTemplateLayout.java
+++ b/log4j-layout-json-template/src/main/java/org/apache/logging/log4j/layout/json/template/JsonTemplateLayout.java
@@ -630,10 +630,13 @@
         public static class Builder
                 implements org.apache.logging.log4j.core.util.Builder<EventTemplateAdditionalField> {
 
+            @org.apache.logging.log4j.plugins.PluginBuilderAttribute
             private String key;
 
+            @org.apache.logging.log4j.plugins.PluginBuilderAttribute
             private String value;
-
+            
+            @org.apache.logging.log4j.plugins.PluginBuilderAttribute
             private Type type = Type.STRING;
 
             public Builder setKey(final String key) {