Fix open twice bug

Author: AustinShalit

ui/src/main/java/edu/wpi/grip/ui/AboutDialogController.java

@@ -72,7 +72,6 @@ void initialize() {
         assert documentationRectangle != null : "fx:id=\"documentationRectangle\" was not injected: check your FXML file 'AboutDialog.fxml'.";
         assert documentationText != null : "fx:id=\"documentationText\" was not injected: check your FXML file 'AboutDialog.fxml'.";
 
-
         versionNumberText.setText("Version " + edu.wpi.grip.core.Main.class.getPackage().getImplementationVersion());
     }
 }

ui/src/main/java/edu/wpi/grip/ui/MainWindowController.java

@@ -217,7 +217,11 @@ public void showProjectSettingsEditor() {
     @FXML
     public void showProjectAboutDialog() throws IOException {
         Stage aboutDialogStage = new Stage();
-        aboutDialogStage.setScene(new Scene(aboutPane));
+        if (aboutPane.getScene() != null) {
+            aboutDialogStage.setScene(aboutPane.getScene());
+        } else {
+            aboutDialogStage.setScene(new Scene(aboutPane));
+        }
         aboutDialogStage.initModality(Modality.APPLICATION_MODAL);
         aboutDialogStage.show();
     }