Bump PG slots max_replication_slots / max_wal_senders = 25 (#1031)

Port PG VM commit 9b7e8b3beed178129f2519313a668e54d5f1216b to K8s.

Co-authored-by: Dragomir Penev <[email protected]>

Author: taurus-forever

src/charm.py

@@ -2133,6 +2133,8 @@ def update_config(self, is_creating_backup: bool = False) -> bool:
         self._patroni.bulk_update_parameters_controller_by_patroni({
             "max_connections": max_connections,
             "max_prepared_transactions": self.config.memory_max_prepared_transactions,
+            "max_replication_slots": 25,
+            "max_wal_senders": 25,
             "shared_buffers": self.config.memory_shared_buffers,
             "wal_keep_size": self.config.durability_wal_keep_size,
         })