disable attestations for PyPI

[dirksammel]

This PR disables attestations for PyPI.

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 63.28%. Comparing base (9d257c1) to head (daac9ec).

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #1028   +/-   ##
=======================================
  Coverage   63.28%   63.28%           
=======================================
  Files          48       48           
  Lines        5965     5965           
  Branches      154      154           
=======================================
  Hits         3775     3775           
  Misses       2190     2190           

Components	Coverage Δ
apel_plugin	74.24% <ø> (ø)
auditor	68.84% <ø> (ø)
auditor_client	94.38% <ø> (ø)
slurm_collector	67.67% <ø> (ø)
slurm_epilog_collector	0.00% <ø> (ø)
htcondor_collector	∅ <ø> (∅)
priority_plugin	37.82% <ø> (ø)