Install test mailer for github bugs

.github/workflows/llvm-bugs.yml

@@ -0,0 +1,57 @@
+name: LLVM Bugs notifier
+
+on:
+  issues:
+    types:
+      - opened
+
+jobs:
+  auto-subscribe:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - uses: actions/setup-node@v2
+        with:
+          node-version: 14
+      - run: npm install mailgun.js form-data
+      - name: Send notification
+        uses: actions/github-script@v5
+        env:
+          MAILGUN_API_KEY: ${{ secrets.LLVM_BUGS_KEY }}
+        with:
+          script: |
+            const Mailgun = require("mailgun.js");
+            const formData = require('form-data');
+            const mailgun = new Mailgun(formData);
+
+            const DOMAIN = "email.llvm.org";
+
+            const mg = mailgun.client({username: 'api', key: process.env.MAILGUN_API_KEY});
+
+            github.rest.issues.get({
+              issue_number: context.issue.number,
+              owner: context.repo.owner,
+              repo: context.repo.repo,
+            })
+            .then(function(issue) {
+              const payload = {
+                author : issue.data.user.login,
+                issue  : issue.data.number,
+                title  : issue.data.title,
+                url    : issue.data.html_url,
+                labels : issue.data.labels.map(label => { return label.name }),
+                assignee : issue.data.assignees.map(assignee => { return assignee.login }),
+                body   : issue.data.body
+              };
+            
+              const data = {
+                from: "LLVM Bugs <llvm-bugs@email.llvm.org>",
+                to: "anton.korobeynikov@llvm.org",
+                subject: `[Bug ${issue.data.number}] ${issue.data.title}`,
+                template: "new-github-issue",
+                'h:X-Mailgun-Variables': JSON.stringify(payload)
+              };
+
+              return mg.messages.create(DOMAIN, data)
+            })
+            .then(msg => console.log(msg));