When has any Arab ever been given a death sentence by Israel?
Until the early 90s some terrorists were sentenced to death without actually being killed of course. I think the last one was a terrorist who bombed a bus (with a planted bomb, not a human bomb) circa 1993. I may be wrong that he was actually sentenced to death but the persecution requested the death penalty (which they no longer do since then).
The only execution in Israel due to court martial was during the war of independence. A Jew, Meir Tobianski, who was suspected of espionage, was tried by a drumhead court martial and was summarily murdered. He was later acquitted, but the senior haganah thugs who murdered him were never punished not even discharged from the army (and quite expectedly, they were subsequently involved in some other high profile fiascoes).