[FIX] compiler: t-model supports radio group in t-foreach

Have a radio group defined inside a t-foreach:
```xml
  <t t-foreach="values" t-as="val" t-key="val">
    <input name="radiogroup" t-att-value="val" t-model="state.radioGroup" />
  </t>
```

Before this commit the algorithm that set the "checked" attribute on the current active
radio button according to the state did not support having a dynamic value (`t-att-value`)

After this commit, this use case works as we go look in the dynamic attributes too.

tests/components/t_model.test.ts

@@ -644,4 +644,35 @@ describe("t-model directive", () => {
     const input = fixture.querySelector("input")!;
     await editInput(input, "Beam me up, Scotty");
   });
+
+  test("t-model with radio button group in t-foreach", async () => {
+    expect.assertions(6);
+    const steps: string[] = [];
+    class SomeComponent extends Component {
+      static template = xml`
+        <div t-on-click="getData" id="get_data">
+          <t t-foreach="options" t-as="opt" t-key="opt">
+            <input type="radio" name="radio_group" t-model="state.group" t-att-value="opt" t-att-id="opt"/>
+          </t>
+        </div>
+      `;
+      state = useState({ group: "scotty" });
+      options = ["beam", "scotty"];
+
+      getData() {
+        steps.push(`group: ${this.state.group}`);
+      }
+    }
+    await mount(SomeComponent, fixture);
+    const divEl = fixture.querySelector("#get_data") as HTMLElement;
+    expect(fixture.querySelector("input:checked")!.getAttribute("id")).toBe("scotty");
+    divEl.click();
+    expect(steps).toEqual(["group: scotty"]);
+    fixture.querySelector("input")!.click();
+    expect(steps).toEqual(["group: scotty", "group: beam"]);
+    await nextTick();
+    expect(fixture.querySelector("input:checked")!.getAttribute("id")).toBe("beam");
+    divEl.click();
+    expect(steps).toEqual(["group: scotty", "group: beam", "group: beam"]);
+  });
 });