Enable redundant_field_names clippy lint

[Dandandan]

Which issue does this PR close?

Closes #260

Rationale for this change

This lint doesn't seem to cause warnings in our code. If we have some false positives, we should not put it here but on a more granular (line/code block/module/project) level, so the warnings locally reflect the CI.
I am not sure why it was configured like this, maybe because of some false positives.

What changes are included in this PR?

Remove the "allow" on the lint

Are there any user-facing changes?

No

[codecov-commenter]

Codecov Report

Merging #261 (a3a0efc) into master (5f6024d) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #261   +/-   ##
=======================================
  Coverage   76.80%   76.80%           
=======================================
  Files         133      133           
  Lines       23284    23284           
=======================================
  Hits        17884    17884           
  Misses       5400     5400           

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[alamb]

Maybe there were false positives in other parts of the arrow codebase as well

[alamb]

Thanks @Dandandan