1. If only read the partition columns, the `JniConnector` will produce empty required fields, so `HudiJniScanner` should read the "_hoodie_record_key" field at least to know how many rows in current hoodie split. Even if the `JniConnector` doesn't read this field, the call of `releaseTable` in `JniConnector` will reclaim the resource.
2. To prevent BE failure and exit, `JniConnector` should call release methods after `HudiJniScanner` is initialized. It should be noted that `VectorTable` is created lazily in `JniScanner`, so we don't need to reclaim the resource when `HudiJniScanner` is failed to initialize.
## Remaining works
Other jni readers like `paimon` and `maxcompute` may encounter the same problems, the jni reader need to handle this abnormal situation on its own, and currently this fix can only ensure that BE will not exit.
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