pgsql: Doc: use "an SQL" consistently rather than "a SQL"

Doc: use "an SQL" consistently rather than "a SQL"

Per the precedent set by 04539e73f, adjust article prefixes for "SQL" to
use "an" consistently rather than "a", i.e., "an es-que-ell" rather than
"a sequel".

Also see b51f86e49, b1b13d2b5, d866f0374 and 7bdd489d3.

Author: David Rowley <dgrowleyml@gmail.com>
Discussion: https://postgr.es/m/CAApHDvp3osQwQam+wNTp9BdhP+QfWO6aY6ZTixQQMfM-UArKCw@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/a78cf591a3f5288aa5ae96902a36e342a3178b79

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