Change “About” and “Privacy policy” links to open in a new tab in advanced interface (#25973)

app/javascript/mastodon/features/getting_started/index.jsx

@@ -142,7 +142,7 @@ class GettingStarted extends ImmutablePureComponent {
 
           {!multiColumn && <div className='flex-spacer' />}
 
-          <LinkFooter />
+          <LinkFooter multiColumn />
         </div>
 
         {(multiColumn && showTrends) && <TrendsContainer />}