pgsql: Add some asserts based on LWLockHeldByMe() for replication slot

Add some asserts based on LWLockHeldByMe() for replication slot statistics

Two assertions checking that ReplicationSlotAllocationLock is acquired
are added to pgstat_create_replslot() and pgstat_drop_replslot(),
corresponding to the routines in charge of the creation and the drop of
replication slot statistics. The code previously relied on this
assumption and documented it in comments, but did not enforce this
policy at runtime.

Reviewed-by: Bertrand Drouvot
Discussion: https://postgr.es/m/Ze_p-hmD_yFeVYXg@paquier.xyz

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/77cf6a78de9fa48976d8c9152a48290beb06dc8b

Modified Files
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src/backend/utils/activity/pgstat_replslot.c | 4 ++++
1 file changed, 4 insertions(+)