MDL-58537 theme_clean: Fix the required field icon

It is a custom sized icon so it needs some custom CSS to size it properly.

theme/bootstrapbase/less/moodle/forms.less

@@ -58,6 +58,10 @@ form {
 }
 .mform .fdescription.required {
     margin-left: @horizontalComponentOffset;
+    & > .icon {
+        width: 8px;
+        height: 12px;
+    }
 }
 .mform .fpassword .unmask {
     display: inline-block;
@@ -87,6 +91,11 @@ form {
 .mform label .req,
 .mform label .adv {
     cursor: help;
+    & > .icon {
+        width: 8px;
+        height: 12px;
+        margin-left: 3px;
+    }
 }
 .mform .fcheckbox input {
     margin-left: 0;

theme/bootstrapbase/style/moodle.css

@@ -16451,6 +16451,10 @@ form {
 .mform .fdescription.required {
   margin-left: 200px;
 }
+.mform .fdescription.required > .icon {
+  width: 8px;
+  height: 12px;
+}
 .mform .fpassword .unmask {
   display: inline-block;
   margin-left: 0.5em;
@@ -16479,6 +16483,12 @@ form {
 .mform label .adv {
   cursor: help;
 }
+.mform label .req > .icon,
+.mform label .adv > .icon {
+  width: 8px;
+  height: 12px;
+  margin-left: 3px;
+}
 .mform .fcheckbox input {
   margin-left: 0;
 }