You must include this in the ssl conf as well:

    <Directory /var/www/mysite.com/mysite-web-app/public>
        Options Indexes FollowSymLinks
        AllowOverride All
        Require all granted
    </Directory>
    <IfModule mod_dir.c>
        DirectoryIndex index.php index.pl index.cgi index.html index.xhtml index.htm
    </IfModule>

Or the .htaccess won’t work for https connections.