Prevent subject and password from being HTML encoded in the invite email (#4301)

Credit to @Pindagus. Related: ac5bc866ff

modules/backend/views/mail/invite.htm

@@ -1,4 +1,4 @@
-subject = "Welcome to {{ appName }}"
+subject = "Welcome to {{ appName | raw }}"
 layout = "system"
 description = "Invite new admin to the site"
 ==
@@ -8,7 +8,7 @@ A user account has been created for you on **{{ appName }}**.
 
 {% partial 'panel' body %}
 - Login: `{{ login ?: 'sample' }}`
-- Password: `{{ password ?: '********' | raw }}`
+- Password: `{{ (password ?: '********') | raw }}`
 {% endpartial %}
 
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