fix: p2p instance test connection

[chlins]

Fix internal server error when test connection to p2p instance with credential.

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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"
• Accepted the DCO. Commits without the DCO will delay acceptance.
• 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 66.17%. Comparing base (c8c11b4) to head (08f1254).
Report is 285 commits behind head on main.

Additional details and impacted files

@@             Coverage Diff             @@
##             main   #20968       +/-   ##
===========================================
+ Coverage   45.36%   66.17%   +20.80%     
===========================================
  Files         244     1048      +804     
  Lines       13333   114471   +101138     
  Branches     2719     2856      +137     
===========================================
+ Hits         6049    75751    +69702     
- Misses       6983    34577    +27594     
- Partials      301     4143     +3842     

Flag	Coverage Δ
unittests	66.17% <100.00%> (+20.80%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files with missing lines	Coverage Δ
src/pkg/p2p/preheat/provider/client/http_client.go	68.61% <100.00%> (ø)
src/pkg/p2p/preheat/provider/dragonfly.go	63.63% <100.00%> (ø)
src/server/v2.0/handler/preheat.go	20.45% <100.00%> (ø)

... and 1284 files with indirect coverage changes

[wy65701436]

lgtm