Cleanup dual target and mono code

Fixes #1893
Fixes #1808

frontend/src/System/Status/About/About.js

@@ -20,7 +20,6 @@ class About extends Component {
       packageVersion,
       packageAuthor,
       isNetCore,
-      isMono,
       isDocker,
       runtimeVersion,
       migrationVersion,
@@ -50,14 +49,6 @@ class About extends Component {
               />
           }
 
-          {
-            isMono &&
-              <DescriptionListItem
-                title={translate('MonoVersion')}
-                data={runtimeVersion}
-              />
-          }
-
           {
             isNetCore &&
               <DescriptionListItem
@@ -121,7 +112,6 @@ About.propTypes = {
   packageVersion: PropTypes.string,
   packageAuthor: PropTypes.string,
   isNetCore: PropTypes.bool.isRequired,
-  isMono: PropTypes.bool.isRequired,
   runtimeVersion: PropTypes.string.isRequired,
   isDocker: PropTypes.bool.isRequired,
   migrationVersion: PropTypes.number.isRequired,