Format externals
  $ refmt ./input.re
  /**
   * Tests external formatting.
   */
  external foo: type_ = "%caml_something_or_other";
  
  external multilineStringExtern: int => int =
    {|
   Did you know you can put whatver you want inside
   of an extern? Good luck with the linker though!
  |};
  
  module Nested = {
    external multilineStringExtern: int => int =
      {|
     Did you know you can put whatver you want inside
     of an extern? Good luck with the linker though!
    |};
    external multilineStringExternWithTag:
      int => int =
      {|
     Did you know you can put whatver you want inside
     of an extern? Good luck with the linker though!
    |};
    external multilineStringExtern: int => int =
      {|
     And this has a newline in it, so will be formatted with { | | } style string|};
    external containsQuote: int => int =
      {|This has a quote in it " so will be formatted as { | | } style string|};
    external noIndentation: int => int =
      {|
  Did you know you can put whatver you want inside
  of an extern? Good luck with the linker though!
  |};
  };
