data source unit tests are broken

[zhouyuan]

Describe the bug
org.apache.spark.SparkException: Job aborted due to stage failure: Task 0 in stage 13.0 failed 1 times, most recent failure: Lost task 0.0 in stage 13.0 (TID 23) (sr404 executor driver): org.apache.arrow.memory.OutOfMemoryException: Not enough spark off-heap execution memory. Acquired: 8388608, granted: 2097152. Try tweaking config option spark.memory.offHeap.size to get larger space to run this application.

To Reproduce
run unit tests on data source

Expected behavior
unit tests passing

Additional context
N/A