fix: different description for non moderator participants in passcode dialog

lang/main.json

         "pullToRefresh": "Pull to refresh"
     },
     "security": {
-        "about": "You can add a passcode to your meeting. Participants will need to provide the passcode before they are allowed to join the meeting.",
+        "about": "You can add a $t(lockRoomPassword) to your meeting. Participants will need to provide the $t(lockRoomPassword) before they are allowed to join the meeting.",
+        "aboutReadOnly": "Moderator participants can add a $t(lockRoomPassword) to the meeting. Participants will need to provide the $t(lockRoomPassword) before they are allowed to join the meeting.",
         "insecureRoomNameWarning": "The room name is unsafe. Unwanted participants may join your conference. Consider securing your meeting using the security button.",
         "securityOptions": "Security options"
     },

react/features/security/components/security-dialog/PasswordSection.js

     return (
         <div className = 'security-dialog password-section'>
             <p className = 'description'>
-                { t('security.about') }
+                { t(canEditPassword ? 'security.about' : 'security.aboutReadOnly') }
             </p>
             <div className = 'security-dialog password'>
                 <div