Save Authenticator configuration in Administration don't work with Tomcat

Step to reproduce:

• Use a XWiki 16.10.8 with Tomcat
• Add a new entry in the configuration with Basic auth
• Set the credential user/password
• Save

Expected

The configuration is saved

Currently

The configuration is not saved and the BasicAuthConfigDisplayer return the error "Invalid CSRF token".

After investigation it seem doing $!request.form_token return nothing with tomcat when the form is send with a multipart/form-data; boundary