Use common subheading on sidebar user settings tab (#8823)

Author: luixxiul

res/css/views/settings/tabs/user/_SidebarUserSettingsTab.scss

@@ -15,17 +15,6 @@ limitations under the License.
 */
 
 .mx_SidebarUserSettingsTab {
-    .mx_SettingsTab_section {
-        margin-top: 12px;
-    }
-
-    .mx_SidebarUserSettingsTab_subheading {
-        font-size: $font-15px;
-        line-height: $font-24px;
-        color: $primary-content;
-        margin-bottom: 4px;
-    }
-
     .mx_Checkbox {
         margin-top: 12px;
         font-size: $font-15px;

src/components/views/settings/tabs/user/SidebarUserSettingsTab.tsx

@@ -55,9 +55,8 @@ const SidebarUserSettingsTab = () => {
     return (
         <div className="mx_SettingsTab mx_SidebarUserSettingsTab">
             <div className="mx_SettingsTab_heading">{ _t("Sidebar") }</div>
-
             <div className="mx_SettingsTab_section">
-                <div className="mx_SidebarUserSettingsTab_subheading">{ _t("Spaces to show") }</div>
+                <div className="mx_SettingsTab_subheading">{ _t("Spaces to show") }</div>
                 <div className="mx_SettingsTab_subsectionText">
                     { _t("Spaces are ways to group rooms and people. " +
                         "Alongside the spaces you're in, you can use some pre-built ones too.") }