Not meant to be a silly question but was it a common name , and as a related question, if it was common when did people stop using it since it was now associated with Christianity?
According to Tal Ilan's Lexicon of Jewish Names in Late Antiquity: Part I: Palestine 330BCE-200AD, Joshua, which - as others here have explained - was Jesus's name, was the the sixth most common name in that five century period, with around 100 documented instances of the roughly 3000 Jewish names she documents from the era.
Related question. What would Jesus name be in whatever language it was spoken at the time?