CI: revert back to dateutil released as many changes

[jreback]

xref #18141

[codecov]

Codecov Report

Merging #18325 into master will decrease coverage by 0.01%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master   #18325      +/-   ##
==========================================
- Coverage   91.38%   91.36%   -0.02%     
==========================================
  Files         164      164              
  Lines       49780    49780              
==========================================
- Hits        45491    45482       -9     
- Misses       4289     4298       +9

Flag	Coverage Δ
#multiple	89.16% <ø> (ø)	⬆️
#single	39.49% <ø> (-0.07%)	⬇️

Impacted Files	Coverage Δ
pandas/io/gbq.py	25% <0%> (-58.34%)	⬇️
pandas/core/frame.py	97.8% <0%> (-0.1%)	⬇️

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