fix: spacing in email

lms/lms/notification/assignment_submission_notification/assignment_submission_notification.md

@@ -2,6 +2,7 @@
     <div style="background-color: #ffffff; width: 75%; margin: 0 auto; padding: 1rem;">
         <h3> {{ _("Assignment Submission") }} </h3>
         {% set title = frappe.db.get_value("Course Lesson", doc.lesson, "title") %}
+        <br>
         <p> {{ _("{0} has submitted their assignment for the lesson {1}").format(frappe.bold(doc.member_name), frappe.bold(title)) }}
         </p>
         <p> {{ _(" Please evaluate and grade the assignment.") }} </p>