chore: add a field released_on_github_by, so the scraper can populate this instead of setting the authors field (#3361)

This is so that the platform releases scraper can automatically add the GitHub handle of the person who made the release to the draft posts it opens. Helps keep track of who made the release, without having to pre-populate the `authors` field.

Author: sabine

tool/ood-gen/lib/platform_release.ml

@@ -11,6 +11,7 @@ type t = {
   contributors : string list;
   project_name : string;
   versions : string list;
+  released_on_github_by : string option;
   github_release_tags : string list;
 }
 [@@deriving of_yaml, show]
@@ -108,6 +109,7 @@ type metadata = {
   versions : string list option;
   experimental : bool option;
   ignore : bool option;
+  released_on_github_by : string option;
   github_release_tags : string list option;
 }
 [@@deriving
@@ -223,17 +225,18 @@ module Scraper = struct
       ^ project ^ "-" ^ github_tag ^ "-draft.md"
     in
     let content = River.content post in
-    let author = River.author post in
+    let released_on_github_by = Some (River.author post) in
     let metadata : metadata =
       {
         title;
         tags;
         contributors = None;
         changelog = None;
         versions = None;
-        authors = Some [ author ];
+        authors = Some [];
         experimental = Some false;
         ignore = Some false;
+        released_on_github_by;
         github_release_tags =
           (match
              List.filter_map (fun (a : string option) -> a) github_release_tags