Artifacts appear while using hard shadows on Metal API. This happens only on Mac 10.12

Steps to reproduce:
1) Open attached project.
2) Open scene "Test" and observe the artifacts.

Alternatively,
1) Create new project > Create Cube > Create plane. Refer Screenshot.
2) Directional Light > Shadow type > Hard Shadows

Actual result: Artifacts occur in the whole scene.

Note: Occurs only on Mac 10.12 and Metal API

Reproducible on : 2018.2.0a5, 2018.1.0b12, 2018.1.0b11, 2018.1.0b5, 2018.1.0b1

Works fine on: 2017.3.0f3, 2017.2.0f3.

Workaround: In directional light under shadow type, increase bias to 0.4