[IMP] add exercise

Author: etobella

docs/playground/playground.js

@@ -104,6 +104,11 @@ const SAMPLES = [
     folder: "oca_07",
     code: ["js", "xml", "css"],
   },
+  {
+    description: "Exercise",
+    folder: "exercise",
+    code: ["js", "xml", "css"],
+  },
   {
     description: "Components",
     folder: "components",

docs/playground/samples/exercise/exercise.css

@@ -0,0 +1,8 @@
+// In this example, we show how components can be defined and created.
+import { Component, useEnv, useSubEnv, useState, mount } from "@odoo/owl";
+
+export class Parent extends Component {
+   static template = 'training_oca.Parent';
+}
+
+mount(Parent, document.body, { templates: TEMPLATES, dev: true });

docs/playground/samples/exercise/exercise.js

@@ -0,0 +1,5 @@
+<templates xml:space="preserve">
+    <t t-name="training_oca.Parent">
+        <div>To Fill</div>
+    </t>
+</templates>