fix(ci): leave milestone assignment to maintainers (#5091)

.github/workflows/action-milestone-sync.yml

@@ -23,7 +23,7 @@ jobs:
     if: github.repository_owner == 'GameServerManagers'
     runs-on: ubuntu-latest
     steps:
-      - name: Set PR milestone and update linked issues
+      - name: Sync selected milestone to linked issues
         uses: actions/github-script@v9
         with:
           script: |
@@ -36,23 +36,7 @@ jobs:
               return;
             }
 
-            let milestone = pr.milestone;
-            if (!milestone && ['opened', 'reopened', 'ready_for_review'].includes(action)) {
-              const open = await github.paginate(github.rest.issues.listMilestones, { owner, repo, state: 'open', per_page: 100 });
-              open.sort((a, b) => {
-                if (a.due_on && b.due_on) return a.due_on.localeCompare(b.due_on);
-                if (a.due_on) return -1;
-                if (b.due_on) return 1;
-                return a.number - b.number;
-              });
-              if (open.length === 0) {
-                core.warning('No open milestone to assign.');
-              } else {
-                milestone = open[0];
-                await github.rest.issues.update({ owner, repo, issue_number: pr.number, milestone: milestone.number });
-                core.info(`Set PR #${pr.number} milestone to ${milestone.title}.`);
-              }
-            }
+            const milestone = pr.milestone;
 
             const body = (pr.body || '').replace(/<!--[\s\S]*?-->/g, '');
             const issueRef = /\b(close[sd]?|fix(?:e[sd])?|resolve[sd]?|related to):?\s+(?:([\w.-]+)\/([\w.-]+))?#(\d+)/gi;