pgsql: Remove sleep() from backup script example; not needed anymore.

Log Message:
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Remove sleep() from backup script example; not needed anymore.

Fujii Masao

Modified Files:
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pgsql/doc/src/sgml:
backup.sgml (r2.127 -> r2.128)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/backup.sgml?r1=2.127&r2=2.128)