[#383] FIX docs: import-ldif and export-ldif binaries should be shown using the --offline option (#385)

Co-authored-by: Maxim Thomas <maxim.thomas@gmail.com>

Author: vharseko

opendj-doc-generated-ref/src/main/docbkx/admin-guide/chap-import-export.xml

@@ -155,6 +155,7 @@ LDIF processing complete.  10003 entries written</screen>
       server, and then run the <command>import-ldif</command> command.</para>
       <screen>$ stop-ds
 $ import-ldif
+ --offline
  --includeBranch dc=example,dc=org
  --backendID userRoot
  --ldifFile /path/to/generated.ldif</screen>
@@ -193,6 +194,7 @@ $ import-ldif
      export data using the <command>export-ldif</command> command.</para>
      <screen>$ stop-ds
 $ export-ldif
+ --offline
  --includeBranch dc=example,dc=org
  --backendID userRoot
  --ldifFile /path/to/backup.ldif</screen>