Reproduction steps:
1. Open attached project.
2. Open "TestScene" scene.
3. Select "Main Camera" game object.
4. Go to "GameObject > Align View To Selected".
5. Resize scene/game view to a small size.
6. Notice the shadowy lines on the "Cube" game object(GIF attached).

Notes:
* The smaller the scene/game view window, the bigger the shadow.
* Shadows are slightly bigger in the scene view than in the game view.
* Not reproducible in the standalone build.

[by design, shadow acne artifacts in some cases]