pgsql: doc: add doc link for 'applicable_roles'

doc: add doc link for 'applicable_roles'

Reported-by: Ashutosh Sharma

Discussion: /messages/by-id/CAE9k0PnhnL6MNDLuvkk8USzOa_DpzDzFQPAM_uaGuXbh9HMKYw@mail.gmail.com

Author: Ashutosh Sharma

Backpatch-through: 9.3

Branch
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REL9_6_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/a65f22fc6223117650fec31a3821f181f15d9366

Modified Files
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doc/src/sgml/information_schema.sgml | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)