doc: Mention PGDATABASE as supported by pgbench
PGHOST, PGPORT and PGUSER were already mentioned, but not PGDATABASE.
Like 5aaa584, backpatch down to 12.
Reported-by: Christophe Courtois
Discussion: https://postgr.es/m/161399398648.21711.15387267201764682579@wrigleys.postgresql.org
Backpatch-through: 12
Branch
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REL_12_STABLE
Details
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https://git.postgresql.org/pg/commitdiff/9e9b5c05010d25e16e04c8c282a52626650ae233
Modified Files
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doc/src/sgml/ref/pgbench.sgml | 13 +++++++++++++
1 file changed, 13 insertions(+)