Wrong output file extension in piping mode

[ym-project]

There is a bug in piping: true mode. https://github.com/ym-project/gulp-esbuild/blob/d101b83b5b10595cd9d5cba430e8380d74402db7/index.js#L212 .js will be generated anyway.

The plugin should respects user settings and sets .js extension only by default.

Also according to the esbuild release, esbuild now supports .mts and .cts extensions. So these extensions should be included too.