Avoid Landing Page Redirects

Hello,

My site is redirecting like this:

http://ironstarrealty.com/
http://www.ironstarrealty.com/
https://www.ironstarrealty.com/

I'm unsure of how to optimize this. I am using the SG Optimizer plugin provided by Siteground which is inserting this code into the htaccess file:

# HTTPS forced by SG-Optimizer
<IfModule mod_rewrite.c>
RewriteEngine On
RewriteCond %{HTTPS} off
RewriteRule ^(.*)$ https://%{SERVER_NAME}%{REQUEST_URI} [R=301,L]
</IfModule>
# END HTTPS

https://gtmetrix.com/reports/ironstarrealty.com/gzgKLjMr

Thank you.