MDL-66999 theme_boost: @extend remove .h2 from calendar

The calendar monthname is already in a <h2>, no additional .h2
styles are needed

theme/boost/scss/moodle/calendar.scss

@@ -213,12 +213,6 @@ $calendarEventUserColor: #dce7ec !default; // Pale blue.
             border-color: $calendarEventUserColor;
         }
 
-        .calendar-controls {
-            .current {
-                @extend .h2;
-            }
-        }
-
         .calendartable {
             td,
             li {

theme/boost/style/moodle.css

@@ -2631,7 +2631,7 @@ template {
   display: none !important; }
 
 h1, h2, h3, h4, h5, h6,
-.h1, .h2, .path-calendar .maincalendar .calendar-controls .current, .h3, .h4, .h5, .h6 {
+.h1, .h2, .h3, .h4, .h5, .h6 {
   margin-bottom: 0.5rem;
   font-weight: 300;
   line-height: 1.2; }
@@ -2639,7 +2639,7 @@ h1, h2, h3, h4, h5, h6,
 h1, .h1 {
   font-size: 2.34375rem; }
 
-h2, .h2, .path-calendar .maincalendar .calendar-controls .current {
+h2, .h2 {
   font-size: 1.875rem; }
 
 h3, .h3 {

theme/classic/style/moodle.css

@@ -2631,7 +2631,7 @@ template {
   display: none !important; }
 
 h1, h2, h3, h4, h5, h6,
-.h1, .h2, .path-calendar .maincalendar .calendar-controls .current, .h3, .h4, .h5, .h6 {
+.h1, .h2, .h3, .h4, .h5, .h6 {
   margin-bottom: 0.5rem;
   font-weight: 300;
   line-height: 1.2; }
@@ -2639,7 +2639,7 @@ h1, h2, h3, h4, h5, h6,
 h1, .h1 {
   font-size: 2.34375rem; }
 
-h2, .h2, .path-calendar .maincalendar .calendar-controls .current {
+h2, .h2 {
   font-size: 1.875rem; }
 
 h3, .h3 {