fix(material/radio): mark radio-group for check on touch (#29203)

Author: mmalerba

src/material/radio/radio.ts

@@ -269,6 +269,7 @@ export class MatRadioGroup implements AfterContentInit, OnDestroy, ControlValueA
   _touch() {
     if (this.onTouched) {
       this.onTouched();
+      this._changeDetector.markForCheck();
     }
   }