fixed a flaky test and let the godot bin be defined by env variable

.runsettings

@@ -6,9 +6,6 @@
         <TargetFrameworks>net8.0;net9.0</TargetFrameworks>
         <TestSessionTimeout>180000</TestSessionTimeout>
         <TreatNoTestsAsError>true</TreatNoTestsAsError>
-        <EnvironmentVariables>
-            <GODOT_BIN>D:\Godot\Godot_v4.6-stable_mono_win64\Godot_v4.6-stable_mono_win64\Godot_v4.6-stable_mono_win64.exe</GODOT_BIN>
-        </EnvironmentVariables>
     </RunConfiguration>
 
     <LoggerRunSettings>

tests/player_movement/PlayerMovementTest.cs

@@ -82,7 +82,7 @@ public class PlayerMovementTest
         var marker = _scene.FindChild(markerName) as Marker3D;
         AssertObject(marker).IsNotNull();
         _player.GlobalPosition = marker!.GlobalPosition;
-        await _runner.AwaitIdleFrame();
+        await _runner.AwaitMillis(100);
         
         var startPos = _player.GlobalPosition;