pgsql: Fix some memory leaks in the WAL receiver

Fix some memory leaks in the WAL receiver

These are old leaks, that can pile up if a WAL receiver stays alive,
waiting for new WAL data after the sender has switched to a new
timeline.

While this is technically a bug, the impact is minimal and would only
become noticeable if the WAL sender handles a lot of timeline switches,
so no backpatch is done. Note that in most cases, primary_conninfo
would be updated in a standby to point to a new sender, meaning a
restart of the WAL receiver. Let's be clean on HEAD, though.

Author: DaeMyung Kang <charsyam(at)gmail(dot)com>
Discussion: https://postgr.es/m/20260426170100.847923-1-charsyam@gmail.com
Discussion: https://postgr.es/m/20260426170219.849330-1-charsyam@gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/b801d5eef17fde6d1311eaefa0f125c55731e30c

Modified Files
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src/backend/replication/walreceiver.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)