Fix course upsell styling when bootstrap is enabled

lms/static/sass/features/_course-upgrade-message.scss

@@ -4,6 +4,14 @@ the creative property. This will allow us to better track individual performance
 Search for the courseware_verified_certificate_upsell promotion ID.
 */
 
+.course-home-sidebar-upgrade .btn-upgrade {
+  padding: 10px 20px;
+}
+
+.course-home-sidebar-upgrade .promo-learn-more {
+  border: none;
+}
+
 .section.section-upgrade {
   border-left: solid 1px #d9d9d9;
   border-bottom: solid 1px #d9d9d9;
@@ -24,6 +32,13 @@ Search for the courseware_verified_certificate_upsell promotion ID.
 .section-upgrade .upgrade-container {
   float: right;
   text-align: center;
+  margin-top: 15px;
+}
+
+@media only screen and (max-width: 991px) and (min-width: 768px)  {
+  .section-upgrade .upgrade-container {
+    float: none;
+  }
 }
 
 .section.section-upgrade p {

lms/templates/courseware/course_navigation.html

@@ -34,7 +34,7 @@ if course is not None:
     tab_list = get_course_tab_list(request, course)
     %>
     % if uses_bootstrap:
-        <nav class="navbar course-tabs pb-0 navbar-expand">
+        <nav class="navbar course-tabs pb-0 navbar-expand" aria-label="${_('Course')}">
             <ul class="navbar-nav mr-auto">
                 % for tab in tab_list:
                     <%

openedx/features/course_experience/__init__.py

@@ -41,7 +41,7 @@ UPGRADE_DEADLINE_MESSAGE = CourseWaffleFlag(WAFFLE_FLAG_NAMESPACE, 'upgrade_dead
 LATEST_UPDATE_FLAG = CourseWaffleFlag(WAFFLE_FLAG_NAMESPACE, 'latest_update')
 
 # Waffle flag to enable the use of Bootstrap for course experience pages
-USE_BOOTSTRAP_FLAG = CourseWaffleFlag(WAFFLE_FLAG_NAMESPACE, 'use_bootstrap')
+USE_BOOTSTRAP_FLAG = CourseWaffleFlag(WAFFLE_FLAG_NAMESPACE, 'use_bootstrap', flag_undefined_default=True)
 
 
 def course_home_page_title(course):  # pylint: disable=unused-argument

openedx/features/course_experience/templates/course_experience/course-home-fragment.html

@@ -114,8 +114,9 @@ from openedx.features.course_experience import UNIFIED_COURSE_TAB_FLAG, SHOW_REV
                 </div>
             % endif
             % if upgrade_url and upgrade_price:
-                <div class="section section-upgrade">
+                <div class="section section-upgrade course-home-sidebar-upgrade">
                     <h3 class="hd hd-6">${_("Pursue a verified certificate")}</h3>
+                        <img src="https://courses.edx.org/static/images/edx-verified-mini-cert.png" alt="">
                         <div class="upgrade-container">
                             <p>
                                 <a class="btn-brand btn-upgrade"
@@ -127,7 +128,6 @@ from openedx.features.course_experience import UNIFIED_COURSE_TAB_FLAG, SHOW_REV
                             </p>
                     <p><button class="btn-link btn-small promo-learn-more">${_('Learn More')}</button></p>
                         </div>
-                        <img src="https://courses.edx.org/static/images/edx-verified-mini-cert.png" alt="">
                 </div>
             % endif
             % if dates_fragment: