feat: extend the p2p preheat policy

[chlins]

Add the field extra_attrs to the p2p preheat policy for the provider to define their specified parameters when preheating.

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Comprehensive Summary of your change

Issue being fixed

Fixes #(issue)

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• Well Written Title and Summary of the PR
• Label the PR as needed. "release-note/ignore-for-release, release-note/new-feature, release-note/update, release-note/enhancement, release-note/community, release-note/breaking-change, release-note/docs, release-note/infra, release-note/deprecation"
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• Made sure tests are passing and test coverage is added if needed.
• Considered the docs impact and opened a new docs issue or PR with docs changes if needed in website repository.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 46.24%. Comparing base (c8c11b4) to head (9d49f1b).
Report is 336 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #21115      +/-   ##
==========================================
+ Coverage   45.36%   46.24%   +0.87%     
==========================================
  Files         244      247       +3     
  Lines       13333    13883     +550     
  Branches     2719     2875     +156     
==========================================
+ Hits         6049     6420     +371     
- Misses       6983     7123     +140     
- Partials      301      340      +39     

Flag	Coverage Δ
unittests	46.24% <ø> (+0.87%)	⬆️

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see 491 files with indirect coverage changes

[stonezdj]

Can you please draft a proposal for this issue?

[chlins]

Proposal: goharbor/community#252