WIP: fix: avoid creating duplicate tooltips in HasTooltip impl

Author: ngonzalezpazFC

src/main/java/com/flowingcode/vaadin/addons/togglebutton/ToggleButton.java

@@ -51,6 +51,7 @@ public class ToggleButton extends AbstractSinglePropertyField<ToggleButton, Bool
         HasThemeVariant<ToggleButtonVariant> {
 
     private ItemLabelGenerator<Boolean> itemLabelGenerator = b -> "";
+    private Tooltip tooltip;
 
     /** Creates a new toggle button with an initial value of {@code false}. */
     public ToggleButton() {
@@ -106,11 +107,21 @@ public boolean isReadOnly() {
 
     @Override
     public Tooltip setTooltipText(String text) {
-        Tooltip tooltip = Tooltip.forComponent(this);
+        if (tooltip == null) {
+            tooltip = Tooltip.forComponent(this);
+        }
         tooltip.setText(text);
         return tooltip;
     }
 
+    @Override
+    public Tooltip getTooltip() {
+        if (tooltip == null) {
+            tooltip = Tooltip.forComponent(this);
+        }
+        return tooltip;
+    }
+
     /**
      * Sets a generator that provides labels for the checked ({@code true}) and unchecked
      * ({@code false}) states. The generator is called with the state value and its result is used