pgsql: Add TAP tests to check replication slot advance during the check

Add TAP tests to check replication slot advance during the checkpoint

The new tests verify that logical and physical replication slots are still
valid after an immediate restart on checkpoint completion when the slot was
advanced during the checkpoint.

This commit introduces two new injection points to make these tests possible:

* checkpoint-before-old-wal-removal - triggered in the checkpointer process
just before old WAL segments cleanup;
* logical-replication-slot-advance-segment - triggered in
LogicalConfirmReceivedLocation() when restart_lsn was changed enough to
point to the next WAL segment.

Discussion: https://postgr.es/m/flat/1d12d2-67235980-35-19a406a0%4063439497
Author: Vitaly Davydov <v(dot)davydov(at)postgrespro(dot)ru>
Author: Tomas Vondra <tomas(at)vondra(dot)me>
Reviewed-by: Alexander Korotkov <aekorotkov(at)gmail(dot)com>
Reviewed-by: Amit Kapila <amit(dot)kapila16(at)gmail(dot)com>
Backpatch-through: 17

Branch
------
master

Details
-------
https://git.postgresql.org/pg/commitdiff/eb124c3d6deb5d0c7a588d847e3840bcc2cd0dcc

Modified Files
--------------
src/backend/access/transam/xlog.c | 4 +
src/backend/replication/logical/logical.c | 18 +++
src/test/recovery/meson.build | 2 +
src/test/recovery/t/046_checkpoint_logical_slot.pl | 139 +++++++++++++++++++++
.../recovery/t/047_checkpoint_physical_slot.pl | 133 ++++++++++++++++++++
5 files changed, 296 insertions(+)