fix: adds a "ring:" prefix to ringid when placing a call

- Prior to commit e4a96e79906b5224375c8897557bbf8361fcb56e,
  newOutgoingCall would use the preferred account to place the
  call even if no uri scheme was detected in the ringId string.

- Adds a break to the end of a switch case for placing a call,
  preventing an the next case(addRingAccount) to be executed each
  call.

Change-Id: I2bce1d78eef4efe7b093b588eb47696f60c606bb
Reviewed-by: Guillaume Roguez <guillaume.roguez@savoirfairelinux.com>

RingD.cpp

@@ -950,7 +950,7 @@ RingD::dequeueTasks()
             break;
         case Request::PlaceCall:
         {
-            auto callId = DRing::placeCall(task->_accountId_new, task->_ringId_new);
+            auto callId = DRing::placeCall(task->_accountId_new, "ring:" + task->_ringId_new);
             CoreApplication::MainView->CoreWindow->Dispatcher->RunAsync(CoreDispatcherPriority::High,
             ref new DispatchedHandler([=]() {
 
@@ -965,6 +965,7 @@ RingD::dequeueTasks()
 
             }));
         }
+        break;
         case Request::AddRingAccount:
         {
             std::map<std::string, std::string> ringAccountDetails;