Fix agent supervisor port using apiserver port instead

[brandond]

Proposed Changes

Fix agent supervisor port using apiserver port instead

The agent's supervisor listener on RKE2 is using the wrong port. Didn't notice it here because they're the same in k3s.

Types of Changes

bugfix

Verification

Can only be tested in RKE2

Testing

Linked Issues

• Expose RKE2 metrics via supervisor port rancher/rke2#5786 (comment)

User-Facing Change

NONE

Further Comments

[codecov]

Codecov Report

Attention: Patch coverage is 50.00000% with 1 line in your changes missing coverage. Please review.

Project coverage is 41.77%. Comparing base (f10cb29) to head (df39266).
Report is 1 commits behind head on master.

Files	Patch %	Lines
pkg/agent/https/https.go	0.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master   #10352      +/-   ##
==========================================
- Coverage   41.78%   41.77%   -0.01%     
==========================================
  Files         177      177              
  Lines       14806    14807       +1     
==========================================
  Hits         6186     6186              
  Misses       7443     7443              
- Partials     1177     1178       +1     

Flag	Coverage Δ
e2etests	36.48% <50.00%> (+0.39%)	⬆️
inttests	36.94% <50.00%> (-0.07%)	⬇️
unittests	11.35% <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.