software/theia: add default configuration for gitlens

So that gitlens extension (which can be installed per-workspace) knows
how to open files from lab.nexedi.com in browser

software/theia/software.cfg

@@ -185,7 +185,8 @@ template =
                       "editor.multiCursorModifier": "ctrlCmd",
                       "editor.tabSize": 2,
                       "plantuml.monochrome": false,
-                      "plantuml.webservice": "//plantuml.host.vifib.net/svg/"
+                      "plantuml.webservice": "//plantuml.host.vifib.net/svg/",
+                      "gitlens.remotes": [{ "domain": "lab.nexedi.com", "type": "GitLab" }]
                   }
               }
           }