Shebang not ignored in ES6 module autodetect

[FergoTheGreat]

Shebang lines are ignored when executing with qjs, allowing for executable JS scripts in *nix environments. However, it seems that the shebang line is not ignored when detecting whether a file is an ES6 module or not. It will look to see if the first line of the file contains an import statement and see the shebang instead and incorrectly conclude that it is not a module.

[bellard]

fixed