Set an upper bound for pyarrow version.

[ueshin]

I'd set the upper bound for pyarrow version for now since we need to set an environment variable to work with pyarrow 0.15.

apache/spark#26045:

Arrow 0.15.0 introduced a change in format which requires an environment variable to maintain compatibility.

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Codecov Report

Merging #918 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #918   +/-   ##
=======================================
  Coverage   94.38%   94.38%           
=======================================
  Files          34       34           
  Lines        6353     6353           
=======================================
  Hits         5996     5996           
  Misses        357      357

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[ueshin]

Thanks! merging.