[C++][R] Should be able to join on keys that are string to large_string type

[asfimport]

Got a report that if your join key is string on one side and large_string on the other, the join doesn't work. It seems reasonable that this should work.

Reporter: Neal Richardson / @nealrichardson

_{Note: This issue was originally created as ARROW-15034. Please see the migration documentation for further details.}

[asfimport]

Jeanette Clark:
I ran into this today - trying to join two arrow datasets together in R using left_join.

Error: Invalid: Incompatible data types for corresponding join field keys: FieldRef.Name(SampleID) of type large_string and FieldRef.Name(SampleID) of type string