[LogsDB] [Stack 8.19.19-SNAPSHOT] [oracle] Failing test daily: system test: (elastic-agent logs - tablespace) in oracle.tablespace

- Stack version: 8.19.19-SNAPSHOT
- LogsDB: enabled
- Package: oracle
- Failing test: system test: (elastic-agent logs - tablespace)
- DataStream: tablespace
- Owners:
- @elastic/obs-infraobs-integrations

Failure:
```
test case failed: one or more errors found while examining elastic-agent.logs4183475646: [0] found error "Unit state changed sql/metrics-default-sql/metrics-oracle-5e6530c9-f785-456c-a365-c3f9ad4e12e3 (HEALTHY->DEGRADED): Error fetching data for metricset sql.query: cannot open connection: testing connection: user=\"sys\" standalone params={authMode:2 connectionClass: connectionClassLength:0 purity:0 newPassword: newPasswordLength:0 appContext: numAppContext:0 externalAuth:0 externalHandle: pool: tag: tagLength:0 matchAnyTag:0 outTag: outTagLength:0 outTagFound:0 shardingKeyColumns: numShardingKeyColumns:0 superShardingKeyColumns: numSuperShardingKeyColumns:0 outNewSession:0}: ORA-12541: TNS:no listener"
```

First build failed: https://buildkite.com/elastic/integrations/builds/46082

Latest 5 failed builds:
- https://buildkite.com/elastic/integrations/builds/46709
- https://buildkite.com/elastic/integrations/builds/46802
- https://buildkite.com/elastic/integrations/builds/46860
- https://buildkite.com/elastic/integrations/builds/46919
- https://buildkite.com/elastic/integrations/builds/47004

Start with the Oracle package's `tablespace` data stream and the `elastic-agent logs - tablespace` system test, using the linked Buildkite failures to reproduce the ORA-12541 no-listener error. Trace the test and Oracle connection setup to identify why the listener is unavailable; done means the test passes reliably in the affected builds.

Written by the indexing model from the issue text.