Update src/main/java/org/kohsuke/github/GHDiscussion.java
Update src/main/java/org/kohsuke/github/GHDiscussion.java

Remove `this.root` as it is already set with the org

Co-authored-by: Liam Newman <13e672715c8d42f4200f35d2b309f553303d2bab@gmail.com>
kohsuke/github-api