## What changes were proposed in this pull request?

This is a follow-up of #18680.

In some environment, a compile error happens saying:

```
.../sql/core/src/main/java/org/apache/spark/sql/execution/vectorized/ArrowColumnVector.java:243:
error: not found: type Array
  public void loadBytes(Array array) {
                        ^
```

This pr fixes it.

## How was this patch tested?

Existing tests.

Author: Takuya UESHIN <ueshin@databricks.com>

Closes #18701 from ueshin/issues/SPARK-21472_fup1.