remove note about Java 9

gradle/content.md

@@ -13,5 +13,3 @@ Note that if you are mounting a volume and the uid running Docker is not `1000`,
 Run this from the directory of the Gradle project you want to build.
 
 `docker run --rm -v "$PWD":/home/gradle/project -w /home/gradle/project %%IMAGE%% gradle <gradle-task>`
-
-**Note: Java 9 support is experimental**

groovy/content.md

@@ -24,5 +24,3 @@ The local Grapes cache can be reused across containers by creating a volume and
 docker volume create --name grapes-cache
 docker run --rm -it -v grapes-cache:/home/groovy/.groovy/grapes %%IMAGE%%
 ```
-
-**Note: Java 9 and Java 10 support is experimental**