pgsql: Prevent non-superusers from reading pg_backend_memory_contexts,

Prevent non-superusers from reading pg_backend_memory_contexts, by default.

pg_backend_memory_contexts view contains some internal information of
memory contexts. Since exposing them to any users by default may cause
security issue, this commit allows only superusers to read this view,
by default, like we do for pg_shmem_allocations view.

Bump catalog version.

Author: Atsushi Torikoshi
Reviewed-by: Michael Paquier, Fujii Masao
Discussion: https://postgr.es/m/1414992.1597849297@sss.pgh.pa.us

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/29dd6d8bc631eebc3e50493c115f7a215f03bd0a

Modified Files
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doc/src/sgml/catalogs.sgml | 4 ++++
src/backend/catalog/system_views.sql | 3 +++
src/include/catalog/catversion.h | 2 +-
3 files changed, 8 insertions(+), 1 deletion(-)