This is quite laughable, since I seriously doubt the Ancient Saxons and Germans who named it 'Easter' in their languages had ever heard of Ishtar. Also, English, German, and a few Slavic tongues are virtually the only languages that so denote it. Most other languages have a name derived from the Greek Πάσχα (Pascha), cognate to the Hebrew פֶּסַח (Pesach), 'Passover' from which the Feast derives and which the Emperor Constantine would have called it.
In fact, even in some dialects of English, it is traditionally called Pasch or Pascha, going back to the Anglo-Saxons over a thousand years ago.
Oh, and BTW, Ishtar is pronounced ˈɪʃtɑːr, not i:tɜ:ʳ