It's not as easy as Introvert and Extrovert, as there are shades of grey in between, so it's worth knowing how you are coming across. From the job description have a think about what degree of extroversion it will require. Your Psychometric Profile will tell an employer about your extroversion in some detail. If you think the job needs more than you have then prepare some examples that illustrate that you could be outgoing when you had to be. Have a look at your CVs & Interviews Report for more insight.