pgsql: doc: Update XID wraparound error example

doc: Update XID wraparound error example

Commit edee0c621de, and the equivalent v17 commit f2353dd71724,
changed the runtime XID wraparound messages to use "transaction IDs"
terminology, but one corresponding error example in maintenance.sgml
still used the older XID wording.

Update that documentation example in line with the current runtime
message.

Backpatch to v17, where the runtime messages were changed.

Author: Fujii Masao <masao(dot)fujii(at)gmail(dot)com>
Reviewed-by: Yugo Nagata <nagata(at)sraoss(dot)co(dot)jp>
Discussion: https://postgr.es/m/CAHGQGwHTN-Xc5iDtbzNSjfxuab5Y9qAArw8cB4PrrDJpZ+1fgA@mail.gmail.com
Backpatch-through: 17

Branch
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REL_18_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/13a9be148e530b9b5c0af2b499e3a08c1f5eb053

Modified Files
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doc/src/sgml/maintenance.sgml | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)