feat: ensure frr_exporter can read ospf socket

- add execute permission to frr socker directory

modules/exporters/manifests/frr_exporter.pp

@@ -16,6 +16,14 @@ class exporters::frr_exporter (
       ensure => installed,
     }
 
+    # ensure the frr_exporter user can read the directory
+    file { $socket_dir:
+      ensure => directory,
+      owner  => 'frr',
+      group  => 'frr',
+      mode   => '0751',
+    }
+
     # manage the user/group
     if $manage_user {
       group { $group: