Optimize linkwarden_web_url concatenation

Improved the readability of the URL construction logic in the linkwarden
role defaults by removing excess whitespace. This change ensures that
the web URL is generated cleanly when the subdomain is present. No
functionality is altered, just a cosmetic fix that enhances code
maintainability.

roles/linkwarden/defaults/main.yml

@@ -29,7 +29,7 @@ linkwarden_paths_folders_list:
 linkwarden_web_subdomain: "{{ linkwarden_name }}"
 linkwarden_web_domain: "{{ user.domain }}"
 linkwarden_web_port: "3000"
-linkwarden_web_url: "{{ 'https://' + (linkwarden_web_subdomain + '.'   + linkwarden_web_domain
+linkwarden_web_url: "{{ 'https://' + (linkwarden_web_subdomain + '.' + linkwarden_web_domain
                      if (linkwarden_web_subdomain | length > 0)
                      else linkwarden_web_domain) }}"