While updating the original (default) domain is not possible, you can add additional internal domains. Once you complete the process of adding the internal domain, it will become the active domain and the site URL within Wordpress will be automatically updated.

Step 1: Navigate to the domains section of the site in question

Step 2: Click the Add Domain button

Step 3: Input the complete domain you need the site to be accessible from

Step 4: Click Check Domain Status button

Step 5: Observe New Domain is now marked Active and Primary

The website will now be accessible on the newly at the newly added domain name. The site url values on the WordPress site itself have been updated automatically.