Discussions plugin: Add upvotes statistics (#469)

source/plugins/discussions/queries/categories.graphql

@@ -5,6 +5,7 @@ query DiscussionsCategories {
         cursor
       }
       nodes {
+        upvoteCount
         category {
           emoji
           name

source/plugins/discussions/queries/comments.graphql

@@ -0,0 +1,12 @@
+query DiscussionsComments {
+  user(login: "$login") {
+    repositoryDiscussionComments($after first: 100) {
+      edges {
+        cursor
+      }
+      nodes {
+        upvoteCount
+      }
+    }
+  }
+}