Should not overwrite buffer when prettier fails to parse file

[mitermayer]

At the moment if we have an invalid file like this we are still overwriting the buffer with the prettier error output.

// @format
const foo x= (a, b) => {};

becomes

stdin: SyntaxError: Unexpected identifier (2:10)
  1 | // @format
> 2 | const foo x= (a, b) => {};
    |           ^
  3 | 

Expected behaviour:

Not overwrite buffer and display an error message