Avoids crashing due to illegal zap address

app/src/main/java/com/vitorpamplona/amethyst/service/lnurl/LightningAddressResolver.kt

@@ -55,6 +55,7 @@ class LightningAddressResolver() {
             return
         }
 
+        try {
             withContext(Dispatchers.IO) {
                 val request: Request = Request.Builder()
                     .header("User-Agent", "Amethyst/${BuildConfig.VERSION_NAME}")
@@ -78,6 +79,9 @@ class LightningAddressResolver() {
                     }
                 })
             }
+        } catch (e: Exception) {
+            onError("Could not resolve $url. Check if the server up and if the lightning address $lnaddress is correct")
+        }
     }
 
     fun fetchLightningInvoice(lnCallback: String, milliSats: Long, message: String, nostrRequest: String? = null, onSuccess: (String) -> Unit, onError: (String) -> Unit) {