Update README.md

[retrocausal]

the parameter passed should be an array and only then does the glob pattern work.

[mahnunchik]

Hi @Nitin-Prabhakar

Both cases work:

1) Just string

return gulp.src('src/**/*.{png,jpg}')

2) Array of strings

return gulp.src(['src/**/*.{png,jpg}'])

So I've decided to close PR. Pls reopen if necessary.