feat: Add loading when retrieving available purchases

Sources/Earthquake Network/Controllers/InApp/SubscriptionsViewController.swift

@@ -38,6 +38,8 @@ class SubscriptionsViewController: UITableViewController {
     private var subscribedProduct: SKProduct?
     /// Availability for subscriptions
     private var availability: EQNPurchaseAvailability?
+    /// Tells if products are loading
+    private var isLoading = false
     
     // MARK: - View Lifecycle
     
@@ -117,7 +119,11 @@ class SubscriptionsViewController: UITableViewController {
     }
     
     private func loadData() {
+        isLoading = true
+        
         VersioneProProducts.store.requestProducts{ [weak self] success, products in
+            self?.isLoading = false
+
             guard let self = self, let products = products, success == true else { return }
             
             // todo: teniamo il più "alto"
@@ -172,7 +178,8 @@ class SubscriptionsViewController: UITableViewController {
     override func tableView(_ tableView: UITableView, viewForHeaderInSection section: Int) -> UIView? {
         let tableSection = sections[section]
         if let cell = tableView.dequeueReusableCell(withIdentifier: "SectionHeaderCell") as? SubscriptionsHeaderTableViewCell {
-            cell.headerTitleLabel.text = tableSection.sectionTitle
+            cell.title = tableSection.sectionTitle
+            cell.isLoading = isLoading
             return cell
         }
         return nil