function Deno.readTextFile
          
readTextFile(path: string | URL,options?: ReadFileOptions,): Promise<string> 
      Asynchronously reads and returns the entire contents of a file as an UTF-8 decoded string. Reading a directory throws an error.
const data = await Deno.readTextFile("hello.txt"); console.log(data);
Requires allow-read permission.
optional
options: ReadFileOptions
      
    Promise<string>