Re-Add demographics prompt to edx.org theme (#24231)

- Add bootstrap utility function to lms-base-v1 CSS
- Moved coaching sass to edx.org theme
- Banner feature flag and MB program gated
- Fixes previous issue of changes specificity in button selector by
  resetting the style inside the component's class

lms/static/sass/base/_build.scss

@@ -7,10 +7,20 @@
 @import 'bootstrap/variables';
 @import 'bootstrap/scss/functions';
 @import 'bootstrap/scss/variables';
+@import 'bootstrap/scss/mixins/background-variant';
 @import 'bootstrap/scss/mixins/box-shadow';
 @import 'bootstrap/scss/mixins/breakpoints';
+@import 'bootstrap/scss/mixins/float';
 @import 'bootstrap/scss/mixins/grid';
+@import 'bootstrap/scss/mixins/hover';
 @import 'bootstrap/scss/mixins/reset-text';
+@import 'bootstrap/scss/mixins/screen-reader';
+@import 'bootstrap/scss/mixins/text-truncate';
+@import 'bootstrap/scss/mixins/text-emphasis';
+@import 'bootstrap/scss/mixins/text-hide';
+@import 'bootstrap/scss/mixins/visibility';
+@import 'bootstrap/scss/utilities';
+
 
 // Bootstrap components
 @import 'bootstrap/scss/popover';

lms/static/sass/elements/_system-feedback.scss

@@ -120,7 +120,7 @@
       box-shadow: none;
       border-top: 1px solid #579cc5;
       padding: 20px 20px 20px 40px;
-      margin: -16px 0 5px 0;
+      margin: -16px 0 10px 0;
     }
 
     .fa-close {

lms/static/sass/multicourse/_dashboard.scss

@@ -525,6 +525,8 @@
     order: 2;
 
     .wrapper-find-courses {
+      margin-bottom: $baseline * 0.5;
+
       .course-advertise {
         @include clearfix();
 
@@ -576,31 +578,9 @@
       }
     }
 
-    .wrapper-coaching {
-      border: 1px solid $border-color-l3;
-      margin: 20px 0;
-
-      .coaching-signup {
-        padding: 20px;
-
-        .coaching-prompt {
-          font-size: 20px;
-          line-height: 28px;
-          font-weight: bold;
-        }
-
-        .coaching-link .btn-neutral {
-          display: block;
-          text-align: center;
-          margin: 20px 20px 0;
-          border-radius: 20px;
-          padding: 10px;
-          border: 1px solid theme-color('primary');
-        }
-      }
-    }
-
     .profile-sidebar {
+      margin-bottom: $baseline * 0.5;
+
       ul {
         padding: 0;
         border: 1px solid theme-color("light");
@@ -609,7 +589,6 @@
 
     // Responsive behavior
     @include media-breakpoint-down(md) {
-      margin: 0 $baseline $baseline*2;
       padding: 0;
       max-width: 100%;
     }