ORC-1696: Fix ClassCastException when reading avro decimal type in be…

…chmark

### What changes were proposed in this pull request?
This PR aims to fix `ClassCastException` when reading avro decimal type in bechmark.

### Why are the changes needed?
ORC-1191 Forcing `object` to `double`, but object type is `ByteBuffer`, which causes scan to fail.

```bash
 java -jar core/target/orc-benchmarks-core-*-uber.jar scan data
```

```java
Exception in thread "main" java.lang.ClassCastException: class java.nio.HeapByteBuffer cannot be cast to class java.lang.Double (java.nio.HeapByteBuffer and java.lang.Double are in module java.base of loader 'bootstrap')
	at org.apache.orc.bench.core.convert.avro.AvroReader$DecimalConverter.convert(AvroReader.java:204)
	at org.apache.orc.bench.core.convert.avro.AvroReader.nextBatch(AvroReader.java:69)
	at org.apache.orc.bench.core.convert.ScanVariants.run(ScanVariants.java:92)
	at org.apache.orc.bench.core.Driver.main(Driver.java:64)
```

### How was this patch tested?
local test
```bash
 java -jar core/target/orc-benchmarks-core-*-uber.jar scan data
```
output
```
data/generated/taxi/avro.snappy rows: 22758236 batches: 22225
```

### Was this patch authored or co-authored using generative AI tooling?
No

Closes #1898 from cxzl25/ORC-1696.

Authored-by: sychen <sychen@ctrip.com>
Signed-off-by: Dongjoon Hyun <dongjoon@apache.org>
(cherry picked from commit d4f13dc)
Signed-off-by: Dongjoon Hyun <dongjoon@apache.org>

java/bench/core/src/java/org/apache/orc/bench/core/convert/avro/AvroReader.java

@@ -41,6 +41,7 @@
 import org.apache.orc.bench.core.convert.BatchReader;
 
 import java.io.IOException;
+import java.math.BigInteger;
 import java.nio.ByteBuffer;
 import java.util.List;
 
@@ -201,7 +202,11 @@ public void convert(ColumnVector cv, int row, Object value) {
         cv.isNull[row] = true;
       } else {
         DecimalColumnVector tc = (DecimalColumnVector) cv;
-        tc.vector[row].set(HiveDecimal.create(Math.round((double) value * multiplier)));
+        if (value instanceof ByteBuffer) {
+          tc.vector[row].set(getHiveDecimalFromByteBuffer((ByteBuffer) value, scale));
+        } else {
+          tc.vector[row].set(HiveDecimal.create(Math.round((double) value * multiplier)));
+        }
       }
     }
   }
@@ -289,6 +294,13 @@ static AvroConverter createConverter(TypeDescription types) {
     }
   }
 
+  static HiveDecimal getHiveDecimalFromByteBuffer(ByteBuffer byteBuffer,
+                                                  int scale) {
+    byte[] result = getBytesFromByteBuffer(byteBuffer);
+    HiveDecimal dec = HiveDecimal.create(new BigInteger(result), scale);
+    return dec;
+  }
+
   static byte[] getBytesFromByteBuffer(ByteBuffer byteBuffer) {
     byteBuffer.rewind();
     byte[] result = new byte[byteBuffer.limit()];