Fix typo

install.lua

@@ -23,7 +23,7 @@ local function main()
   if not fs.exists("sha256.lua") then
     log.info("Downloading sha256.lua")
     local sharequest = http.get(URLs.sha256)
-    local shafile = fs.open("sha2.lua", "w")
+    local shafile = fs.open("sha256.lua", "w")
     shafile.write(sharequest.readAll())
     shafile.close()
     sharequest.close()