[wpilib] LinearOpMode: wait for mode change to return from OpModeRun (#8477)

We need to wait, or otherwise OpModeRobot will immediately reinstantiate
and re-run the opmode, which is generally undesirable (e.g. for
autonomous).

Fixes #8475.

wpilibj/src/main/java/org/wpilib/opmode/LinearOpMode.java

@@ -67,6 +67,12 @@ public abstract class LinearOpMode implements OpMode {
 
     try (DriverStationModeThread bgThread = new DriverStationModeThread(word)) {
       run();
+
+      // Wait for opmode to be stopped or disabled, otherwise OpModeRobot will recreate and re-run
+      // the opmode immediately.
+      while (isRunning() && DriverStation.isEnabled() && DriverStation.getOpModeId() == opModeId) {
+        Thread.sleep(20);
+      }
     }
   }