chore: add engagement codeowners

Author: samir-acle

.github/CODEOWNERS

@@ -153,6 +153,10 @@ app/components/Views/Settings/NotificationsSettings @MetaMask/notifications
 **/notifications/** @MetaMask/notifications
 **/notification/** @MetaMask/notifications
 
+# Engagement Team
+**/Engagement/** @MetaMask/engagement
+**/engagement/** @MetaMask/engagement
+
 # LavaMoat Team
 ses.cjs                              @MetaMask/supply-chain
 patches/react-native+0.*.patch       @MetaMask/supply-chain