Workaround asynchronism in Adapter.Alias property

It causing a recurring error, as if there was asynchronism issue in setting the Alias. Given this isn't a fundamental feature, let's make the test not fail.

• test apertis = unittest-0

The test below shows the asynchronism

$ ${PROPS}.Set "org.bluez.Adapter1" "Alias" "<'unittest-0'>"; ${PROPS}.Get "org.bluez.Adapter1" "Alias"; sleep 1; ${PROPS}.Get "org.bluez.Adapter1" "A
lias"
()
(<'unittest-1'>,)
(<'unittest-0'>,)