SOV-4461: Remove POWA page (#1014)

* Remove POWA page

* Create lovely-buses-greet.md

* Delete obsolete translations

Author: tiltom

.changeset/lovely-buses-greet.md

@@ -0,0 +1,5 @@
+---
+"frontend": patch
+---
+
+SOV-4461: Remove POWA page

apps/frontend/src/app/3_organisms/Header/Header.constants.tsx

@@ -59,11 +59,6 @@ export const menuItemsMapping: MenuItem[] = [
         label: t(translations.header.nav.earn.subMenu.stakingDescription),
         url: '/earn/staking',
       },
-      {
-        text: t(translations.leaderboardPage.headerLink),
-        label: t(translations.leaderboardPage.headerDescription),
-        url: '/powa',
-      },
     ],
   },
   {