fix: telemetry does not use proxy agent

[rix0rrr]

We instantiated the proxy agent correctly, but forgot to pass it to the telemetry backend.

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[github-actions]

Dependency Review

✅ No vulnerabilities or license issues or OpenSSF Scorecard issues found.

Scanned Files

None

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 88.18%. Comparing base (6800788) to head (7870c5c).

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #1577   +/-   ##
=======================================
  Coverage   88.18%   88.18%           
=======================================
  Files          76       76           
  Lines       10841    10841           
  Branches     1493     1493           
=======================================
  Hits         9560     9560           
  Misses       1253     1253           
  Partials       28       28           

Flag	Coverage Δ
suite.unit	88.18% <100.00%> (ø)

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