feat: Revert disable stx opt-in modal (#24715) (#24845)

Once this is merged, this PR will be cherry-picked into 11.16.1

This reverts commit 20e51e6.

Per discussion relating to the feature flag http request for stx, we are
re-enabling the stx opt-in-modal.

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ui/pages/home/home.component.js

@@ -846,10 +846,8 @@ export default class Home extends PureComponent {
       !process.env.IN_TEST &&
       !newNetworkAddedConfigurationId;
 
-    // TODO(dbrans): temporary fix to disable the smart transactions opt-in modal
-    // in 11.15 to unblock the release. Change this line in 11.16.
     const showSmartTransactionsOptInModal =
-      false && canSeeModals && isSmartTransactionsOptInModalAvailable;
+      canSeeModals && isSmartTransactionsOptInModalAvailable;
 
     const showWhatsNew =
       canSeeModals &&