docs: improve English in config.js

config.js

     // and microsoftApiApplicationClientID
     // enableCalendarIntegration: false,
 
-    // When 'true', it shows an intermediate page before joining, where the user can  configure its devices.
+    // When 'true', it shows an intermediate page before joining, where the user can configure their devices.
     // prejoinPageEnabled: false,
 
     // If true, shows the unsafe roon name warning label when a room name is
     // callStatsID: '',
     // callStatsSecret: '',
 
-    // enables sending participants display name to callstats
+    // Enables sending participants' display names to callstats
     // enableDisplayNameInStats: false,
 
-    // enables sending participants email if available to callstats and other analytics
+    // Enables sending participants' emails (if available) to callstats and other analytics
     // enableEmailInStats: false,
 
     // Privacy