pgsql: doc: Remove one example related to pg_input_error_info()

doc: Remove one example related to pg_input_error_info()

This slightly bloated the contents of the function table for this entry,
without really bringing extra value.

Per discussion with Jian He and David G. Johnston.

Discussion: /messages/by-id/CACJufxGdyoBJQMSxwdxNK=k8M5WUth5FDFd4Wq_K4f7+1J2xuQ@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/f6ab942f5de003f37b88580154ebb614655d7e11

Modified Files
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doc/src/sgml/func.sgml | 11 +----------
1 file changed, 1 insertion(+), 10 deletions(-)