Update spec/classes/foreman_proxy__spec.rb

Co-authored-by: Ewoud Kohl van Wijngaarden <ewoud@kohlvanwijngaarden.nl>

Author: Bastian Schmidt

spec/classes/foreman_proxy__spec.rb

@@ -467,7 +467,7 @@
               ':enabled: https',
               ':tftproot: /tftproot',
               ':tftp_servername: 127.0.1.1',
-              ':system_image_root: /var/lib/foreman-proxy/tftp/system_images}'
+              ':system_image_root: /var/lib/foreman-proxy/tftp/system_images'
             ])
           end
         end