The IDL compiler currently throws a "duplicate symbol" error when we specify the same string for one command's command_name and another's command_alias. This error is not present when the same string is specified for one command's command_name and another command's command_name. 

Option A (throws error):
clusterMergeChunks:
command_name: mergeChunks
cpp_name: ClusterMergeChunks

_shardsvrMergeChunks:
command_name: _shardsvrMergeChunks
command_alias: mergeChunks
cpp_name: ShardsvrMergeChunks

Option B (no error):
clusterMergeChunks:
command_name: mergeChunks
cpp_name: ClusterMergeChunks

_shardsvrMergeChunks:
command_name: mergeChunks
command_alias: _shardsvrMergeChunks
cpp_name: ShardsvrMergeChunks

We should remove the duplicate check for commands since the IDL doesn't have a holistic view of all the command names anyways. We should also investigate why this is the case.