pgsql: Remove redundant privilege check from pg_sequences system view.

Remove redundant privilege check from pg_sequences system view.

This commit adjusts pg_sequence_last_value() to return NULL instead
of ERROR-ing for sequences for which the current user lacks
privileges. This allows us to remove the call to
has_sequence_privilege() in the definition of the pg_sequences
system view.

Bumps catversion.

Suggested-by: Michael Paquier
Reviewed-by: Michael Paquier, Tom Lane
Discussion: https://postgr.es/m/20240501005730.GA594666%40nathanxps13

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/7967d10c5b49ccb82f67a0b80678a1a932bccdee

Modified Files
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src/backend/catalog/system_views.sql | 6 +-----
src/backend/commands/sequence.c | 12 ++++--------
src/include/catalog/catversion.h | 2 +-
src/test/regress/expected/rules.out | 5 +----
4 files changed, 7 insertions(+), 18 deletions(-)