pgsql: doc: clarify create database in start docs uses command line

doc: clarify create database in start docs uses command line

Reported-by: vrms@netcologne.de

Discussion: /messages/by-id/172251463564.915373.17748961617119647662@wrigleys.postgresql.org

Backpatch-through: master

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/cf3bb262044a741a47ff40080b145fe432c54407

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