Fix validation logic in Stimulus comments controller

Fixed bug where validation errors for both empty fields were not being
displayed correctly. Changed else-if to if so both Author and Text
validation errors can be added when both fields are empty.

This fixes the failing Stimulus/Turbo tests.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

Author: justin808

client/app/controllers/comments_controller.js

@@ -22,10 +22,8 @@ export default class extends Controller {
       errorList.innerHTML = '';
       if (!inputAuthor.value) {
         errors.push('Author');
-      } else if (!inputText.value) {
-        errors.push('Text');
-      } else {
-        errors.push('Author');
+      }
+      if (!inputText.value) {
         errors.push('Text');
       }
       errors.forEach((error) => {