HashDistributionSpec:
+ See https://iceberg.apache.org/docs/1.6.0/spark-writes/#writing-distribution-modes 
Using write.distribution-mode
- should create the appropriate number of Iceberg files
  + Given a table that is created with:
CREATE TABLE polaris.my_namespace.HashDistributionSpec (
  id int,
  label String,
  partitionKey long,
  date Date,
  timestamp Timestamp
) USING iceberg TBLPROPERTIES (
  'format-version' = '2',
  'write.distribution-mode' = 'hash'
) PARTITIONED BY (partitionKey); 
  + And it has 20 rows over 5 data files when writing with 4 executor threads 
  + When we add another 20 rows of the same data that is logically distributed over 5 partitions 
  + Then there are now 5 more data files 
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +  
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +  
Run completed in 26 seconds, 514 milliseconds.
Total number of tests run: 30
Suites: completed 15, aborted 0
Tests: succeeded 30, failed 0, canceled 0, ignored 4, pending 0
All tests passed.