fix(installers): don't warn when overwriting its own symlink on install with cache enabled (fixes #2502)

[noirbizarre]

Pull Request Checklist

• A news fragment is added in news/ describing what is new.
• Test cases added for changed code: N/A

Describe what you have changed in this PR.

This PR ensure that pdm does not raise warning on install/update for symlinks it created himself when cache is enabled.

Fixes #2502

[codecov]

Codecov Report

Attention: 2 lines in your changes are missing coverage. Please review.

Comparison is base (1af8d29) 84.64% compared to head (456c5b0) 84.63%.
Report is 1 commits behind head on main.

Files	Patch %	Lines
src/pdm/installers/installers.py	0.00%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2503      +/-   ##
==========================================
- Coverage   84.64%   84.63%   -0.01%     
==========================================
  Files         104      104              
  Lines       10335    10336       +1     
  Branches     2258     2259       +1     
==========================================
  Hits         8748     8748              
- Misses       1115     1116       +1     
  Partials      472      472              

Flag	Coverage Δ
unittests	84.42% <0.00%> (-0.01%)	⬇️

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

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.