[CHORE] [Hotfix] Remove pyarrow upper bound for Windows.

[clarkzinzow]

The pyarrow < 7.0.0 upper bound is needlessly restrictive, since

1. Ray already has that upper-bound since their pickle bug workaround doesn't work for Windows, so if a Windows user is using Ray + Daft, their pyarrow should already satisfy that upper bound.
2. If a user isn't using Ray, then they shouldn't need that upper bound anyway, since we're not using pyarrow + pickle when only using the local runner.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 84.70%. Comparing base (118e141) to head (e1d1b53).

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #2002   +/-   ##
=======================================
  Coverage   84.70%   84.70%           
=======================================
  Files          58       58           
  Lines        6363     6363           
=======================================
  Hits         5390     5390           
  Misses        973      973