[mac] github verification build fails randomly

[jukzi]

MAC only: On the first run "Verify MacOS with Java-17" almost always fails with
71 errors like

expected:<Shell {} [layout=null]> but was:<null>
java.lang.AssertionError: expected:<Shell {} [layout=null]> but was:<null>
	at org.junit.Assert.fail(Assert.java:89)
	at org.junit.Assert.failNotEquals(Assert.java:835)
	at org.junit.Assert.assertEquals(Assert.java:120)
	at org.junit.Assert.assertEquals(Assert.java:146)

After a Re-run of failed jobs sometimes all tests pass: