fix load command example (#1967)

without extra flag got:

```
Failed to load database 'system': Database already exists: systemLoad failed for databases: 'system'
Load failed for databases: 'system'
```

Author: iamolegga

modules/ROOT/pages/kubernetes/operations/dump-load.adoc

@@ -31,7 +31,7 @@ For information about the command syntax, options, and usage, see xref:backup-re
 +
 [source, shell]
 ----
-neo4j-admin database load --expand-commands system --from-path=/backups && neo4j-admin database load --expand-commands neo4j --from-path=/backups
+neo4j-admin database load --expand-commands system --from-path=/backups --overwrite-destination=true && neo4j-admin database load --expand-commands neo4j --from-path=/backups --overwrite-destination=true
 ----
 +
 [TIP]
@@ -40,4 +40,4 @@ For information about the command syntax, options, and usage, see xref:backup-re
 ====
 +
 . Put your Neo4j back to xref:kubernetes/operations/maintenance-mode.adoc#put-online-mode[online mode].
-. Verify that Neo4j is working by refreshing Neo4j Browser.
+. Verify that Neo4j is working by refreshing Neo4j Browser.