The top and botton values of rect transform are slowly incrementing when changing UI Image's alpha channel in the animation

Steps to reproduce this issue:

1. Import the attached package (case_677106)
2. Open 'Main Menu' scene
3. Select Image gameobject (Main Camera->Canvas->Main Panel->Buttons Panel->Title->Image)
4. Play the scene
5. Notice 'Image' rect transform's top/bottom values changing even though animation only changes alpha value

Workaround: Disabaling the animation, or adding a curve to the animation to force Top and Bottom values fixes the problem.