fix: packages/email-server/package.json to reduce vulnerabilities

The following vulnerabilities are fixed with an upgrade:
- https://snyk.io/vuln/SNYK-JS-TAR-15127355
- https://snyk.io/vuln/SNYK-JS-NEXT-15104645

Author: snyk-bot

packages/email-server/package.json

@@ -36,7 +36,7 @@
     "async": "^3.2.4",
     "axios": "^0.27.2",
     "bufferutil": "^4.0.7",
-    "canvas": "^2.10.2",
+    "canvas": "^3.0.0",
     "cron": "^2.1.0",
     "dotenv": "^16.0.3",
     "encoding": "^0.1.13",
@@ -51,7 +51,7 @@
     "mjml": "^4.13.0",
     "mjml-react": "^2.0.8",
     "mysql2": "^2.3.3",
-    "next": "^v12.3.2",
+    "next": "^15.5.10",
     "nodemailer": "^6.8.0",
     "nodemailer-postmark-transport": "^5.2.1",
     "octokit": "^2.0.10",