Correct email settings URL and rename variable.

TNL-2677

lms/djangoapps/bulk_email/admin.py

@@ -36,7 +36,8 @@ Other tags that may be used (surrounded by one curly brace on each side):
 {course_title}         : the name of the course
 {course_url}           : the course's full URL
 {email}                : the user's email address
-{account_settings_url} : URL at which users can change email preferences
+{account_settings_url} : URL at which users can change account preferences
+{email_settings_url}   : URL at which users can change course email preferences
 {course_image_url}     : URL for the course's course image.
     Will return a broken link if course doesn't have a course image set.
 

lms/djangoapps/bulk_email/fixtures/plain-html.txt

@@ -242,7 +242,7 @@
 <br>
 This email was automatically sent from {platform_name}. <br>
 You are receiving this email at address {email} because you are enrolled in <a href='{course_url}'>{course_title}</a>.<br>
-To stop receiving email like this, update your course email settings <a href='{account_settings_url}'>here</a>. <br>
+To stop receiving email like this, update your course email settings <a href='{email_settings_url}'>here</a>. <br>
                         </td>
                     </tr>
                 </tbody></table>

lms/djangoapps/bulk_email/tasks.py

@@ -160,6 +160,7 @@ def _get_course_email_context(course):
         'course_image_url': image_url,
         'course_end_date': course_end_date,
         'account_settings_url': 'https://{}{}'.format(settings.SITE_NAME, reverse('account_settings')),
+        'email_settings_url': 'https://{}{}'.format(settings.SITE_NAME, reverse('dashboard')),
         'platform_name': settings.PLATFORM_NAME,
     }
     return email_context

lms/djangoapps/bulk_email/tests/test_models.py

@@ -83,7 +83,7 @@ class CourseEmailTemplateTest(TestCase):
         context = {
             'course_title': "Bogus Course Title",
             'course_url': "/location/of/course/url",
-            'account_settings_url': "/location/of/account/settings/url",
+            'email_settings_url': "/location/of/email/settings/url",
             'platform_name': 'edX',
             'email': 'your-email@test.com',
         }