Let RadioButtonCtsActivity opt-out edge-to-edge enforcement

This is a temporary solution to prevent breaking test failures while
enabling the feature flag of the edge-to-edge enforcement.

We still need to make activities handle insets properly later.

Fix: 330955403
Bug: 309578419
Flag: com.android.window.flags.enforce_edge_to_edge
Test: atest RadioButtonTest
Change-Id: Iec9f8e4c1f6722e733a05ae63de33ff315de4d27