apply path to correct exec resource

manifests/install.pp

@@ -86,6 +86,7 @@ class matlab::install(      # $namevar matlab release version
   exec {"mount -t iso9660 -o loop,ro ${vardir}/MATHWORKS-${name_}.iso /mnt/matlab-${name_}" :
     alias   => "matlab_mount.${name_}",
     unless  => "test -e ${install_destination}/bin/matlab",
+    path      => ['/usr/bin', '/bin'],
     require => [File["matlab_iso.${name_}"]]
   }
 
@@ -105,7 +106,6 @@ class matlab::install(      # $namevar matlab release version
     logoutput => on_failure,
     creates   => $install_destination,  # when this folder appears, we assume it got installed
     require   => File["matlab_input.${name_}"],
-    path      => ['/usr/bin', '/bin'],
     alias     => "matlab_install.${name_}",
     timeout   => 3600,
   }