chore(github-workflow): add linear: next labels to sync popular issues to linear (vercel#65288)

## Why?

Helps us triage the most popular issues better by also having these in
linear.

Closes NEXT-3290

Author: samcx

.github/actions/next-repo-info/dist/issues/index.mjs

@@ -10,7 +10,7 @@ function generateBlocks(issues) {
       type: 'section',
       text: {
         type: 'mrkdwn',
-        text: '*A list of the top 15 issues sorted by the most reactions over the last 90 days.*\n_Note: This :github2: <https://github.com/vercel/next.js/blob/canary/.github/workflows/popular.yml|workflow> → <https://github.com/vercel/next.js/blob/canary/.github/actions/next-repo-info/src/popular-issues.mjs|action> will run every Monday at 10AM UTC (6AM EST)._',
+        text: '*A list of the top 15 issues sorted by the most reactions over the last 90 days.*\n_Note: This :github2: <https://github.com/vercel/next.js/blob/canary/.github/workflows/popular.yml|workflow> → <https://github.com/vercel/next.js/blob/canary/.github/actions/next-repo-info/src/popular-issues.mjs|action> will run every Monday at 10AM UTC (6AM EST). These issues are automatically synced to Linear._',
       },
     },
     {
@@ -54,6 +54,15 @@ async function run() {
     })
 
     if (data.items.length > 0) {
+      data.items.forEach(async (item) => {
+        await octoClient.rest.issues.addLabels({
+          owner,
+          repo,
+          issue_number: item.number,
+          labels: ['linear: next'],
+        })
+      })
+
       await slackClient.chat.postMessage({
         blocks: generateBlocks(data.items),
         channel: '#team-next-js',