pgsql: doc: Remove stray word from pg_stash_advice docs.

doc: Remove stray word from pg_stash_advice docs.

Commit c10edb102ada607eb054bc9e23690109d86849ef left behind the
word "both" where it no longer makes sense.

Reported-by: Erik Rijkers <er@xs4all.nl>
Discussion: http://postgr.es/m/8912b2e5-ccad-4cbd-ab53-869b0b9ecec5@xs4all.nl

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/e89f98ff035fa56ff288ff2407f3eceddf187d70

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