Clarify that RestTemplateBuilder overwrites default converters

See gh-13714

Author: weltonrodrigo

spring-boot/src/main/java/org/springframework/boot/web/client/RestTemplateBuilder.java

@@ -201,7 +201,8 @@ public RestTemplateBuilder messageConverters(
 
 	/**
 	 * Add additional {@link HttpMessageConverter HttpMessageConverters} that should be
-	 * used with the {@link RestTemplate}.
+	 * used with the {@link RestTemplate}. The final list of converters replace any
+	 * RestTemplate came configured with.
 	 * @param messageConverters the converters to add
 	 * @return a new builder instance
 	 * @see #messageConverters(HttpMessageConverter...)
@@ -214,7 +215,8 @@ public RestTemplateBuilder additionalMessageConverters(
 
 	/**
 	 * Add additional {@link HttpMessageConverter HttpMessageConverters} that should be
-	 * used with the {@link RestTemplate}.
+	 * used with the {@link RestTemplate}. The final list of converters replace any
+	 * RestTemplate came configured with.
 	 * @param messageConverters the converters to add
 	 * @return a new builder instance
 	 * @see #messageConverters(HttpMessageConverter...)