feat: support co-authorship lines in body

Author: JakobJingleheimer

lib/rules/line-length.js

@@ -29,10 +29,14 @@ export default {
     let failed = false
     for (let i = 0; i < parsed.body.length; i++) {
       const line = parsed.body[i]
+
       // Skip quoted lines, e.g. for original commit messages of V8 backports.
       if (line.startsWith('    ')) { continue }
       // Skip lines with URLs.
       if (/https?:\/\//.test(line)) { continue }
+      // Skip co-authorship.
+      if (line.startsWith('Co-Authored-By')) { continue }
+
       if (line.length > len) {
         failed = true
         context.report({