message: Add icon for Gulpfile.mjs
  Gulp supports the `.mjs` file extension for config files (tracked at https://github.com/gulpjs/interpret/issues/65).
  It looks like `.cjs` is not supported yet (https://github.com/gulpjs/interpret/issues/68).
diff: @@ -1731,7 +1731,7 @@ export const extensions: IFileCollection = {
  icon: 'gulp',
  extensions: [],
  filenamesGlob: ['gulpfile', 'gulpfile.esm', 'gulpfile.babel'],
  - extensionsGlob: ['js', 'coffee', 'ts'],
  + extensionsGlob: ['js', 'coffee', 'ts', 'mjs'],
  filename: true,
  format: FileFormat.svg,
  },
  