remove course list bottom padding (#4497)

to mimic chat list and allow each scrollable widget to reach the bottom of the screen

lib/pangea/chat_settings/pages/pangea_room_details.dart

@@ -41,7 +41,8 @@ class PangeaRoomDetailsView extends StatelessWidget {
                         const Center(child: BackButton()),
                   ),
             body: Padding(
-              padding: const EdgeInsetsGeometry.all(16.0),
+              padding: const EdgeInsetsGeometry.only(
+                  top: 16.0, left: 16.0, right: 16.0),
               child: MaxWidthBody(
                 maxWidth: 900,
                 showBorder: false,

lib/pangea/course_chats/course_chats_view.dart

@@ -51,9 +51,10 @@ class CourseChatsView extends StatelessWidget {
         final isColumnMode = FluffyThemes.isColumnMode(context);
         return Padding(
           padding: isColumnMode
-              ? const EdgeInsets.symmetric(
-                  vertical: 12.0,
-                  horizontal: 8.0,
+              ? const EdgeInsets.only(
+                  top: 12.0,
+                  left: 8.0,
+                  right: 8.0,
                 )
               : const EdgeInsets.all(0.0),
           child: ListView.builder(