electron-builder: Add '--no-sandbox' launch arg for Linux build targets

Fixes Dev Tools not being able to be opened, among other subtle issue.

This is a frequently reported bug, and we try to apply this workaround
elsewhere, it's just that the .desktop file that electron-builder
generates skips the workaround we have applie e.g. in the /us/bin/pulsar
launcher script.

script/electron-builder.js

@@ -176,6 +176,7 @@ let options = {
         "to": "pulsar.svg"
       },
     ],
+    "executableArgs": ['--no-sandbox'],
   },
   "mac": {
     "icon": icnsIcon,