fix threading issue

Session/Home/HomeVC.swift

@@ -152,7 +152,7 @@ final class HomeVC : BaseVC, UITableViewDataSource, UITableViewDelegate, NewConv
         // Re-populate snode pool if needed
         SnodeAPI.getSnodePool().retainUntilComplete()
         // Onion request path countries cache
-        DispatchQueue.global(qos: .utility).async {
+        DispatchQueue.global(qos: .utility).sync {
             let _ = IP2Country.shared.populateCacheIfNeeded()
         }
         // Get default open group rooms if needed

Session/Utilities/IP2Country.swift

@@ -46,7 +46,8 @@ final class IP2Country {
     }
 
     @objc func populateCacheIfNeededAsync() {
-        IP2Country.workQueue.async {
+        // This has to be sync since the `countryNamesCache` dict doesn't like async access
+        IP2Country.workQueue.sync {
             let _ = self.populateCacheIfNeeded()
         }
     }