small ux correction when model loading fails

Author: carlosuc3m

src/main/java/ai/nets/samj/gui/MainGUI.java

@@ -244,6 +244,7 @@ protected void loadModel() {
                 cmbModels.getSelectedModel().setReturnOnlyBiggest(retunLargest.isSelected());
                 setTwoThirdsEnabled(true);
             } catch (IOException | RuntimeException | InterruptedException ex) {
+                go.setEnabled(true);
                 ex.printStackTrace();
             }
             this.go.showAnimation(false);