fix: de-dupe release notes in each PR

lib/workers/pr/index.js

@@ -148,6 +148,19 @@ async function ensurePr(prConfig) {
   config.hasReleaseNotes = config.upgrades.some(upg => upg.hasReleaseNotes);
   config.hasCommits = config.upgrades.some(upg => upg.hasCommits);
 
+  const releaseNoteRepos = [];
+  for (const upgrade of config.upgrades) {
+    if (releaseNoteRepos.includes(upgrade.repositoryUrl)) {
+      logger.debug(
+        { depName: upgrade.depName },
+        'Removing duplicate release notes'
+      );
+      upgrade.hasReleaseNotes = false;
+    } else {
+      releaseNoteRepos.push(upgrade.repositoryUrl);
+    }
+  }
+
   const prTitle = handlebars.compile(config.prTitle)(config);
   let prBody = handlebars.compile(config.prBody)(config);
   if (config.isGitHub && !config.privateRepo) {