feat(datafusion): Add IcebergCommitExec to commit the written data files (apache#1588)

## Which issue does this PR close?

- Closes apache#1546 
- Draft: apache#1511 

## What changes are included in this PR?
- Added `IcebergCommitExec` to help commit the data files written and
return the number of rows written


## Are these changes tested?
Added ut

Author: CTTY