Accept duplicated keys from Arrow::Table

[heronshoes]

Arrow::Table accepts duplicated keys but RedAmber::DataFrame doesn't.

table = Arrow::Table.new([[:x, [1,2,3]], [:x, [4,5,6]]])
# =>
#<Arrow::Table:0x7fdc282d0e18 ptr=0x5638152d3040>                             
        x       x                                                             
0       1       4                                                             
1       2       5                                                             
2       3       6

RedAmber::DataFrame.new(table)
# =>
/someplace/red_amber/lib/red_amber/data_frame.rb:690:in `check_duplicate_keys': duplicate keys: [:x] (RedAmber::DataFrameArgumentError)                                                                  
        from /someplace/red_amber/lib/red_amber/data_frame.rb:114:in `initialize'                                          
        from (irb):10:in `new'                                                
        from (irb):10:in `<main>'                          
        from bin/console:15:in `<main>'

We have key renaming mechanism in join. Is it useful to accept these keys by renaming?