Good news - you don't have to!  You can update your Lightspeed integration setting in RTK to prevent the need to log in each time.  To update this setting, log in to LSC and view a product page.  Take note of and copy the URL subdomain and domain of the URL when you view a product.  

Log into RTK and navigate to Integrations > Lightspeed Cloud Settings

On the Cloud Settings page, review the URL in the "Base URL for Product Pages" field.  Edit the URL in that field to update the subdomain and domain to reflect what you copied when logged into LSC.  Please only update the subdomain and domain; do not change the rest of the URL as it is required to navigate to the product page.