chore: agent state wasn't getting deleted and logged error

[NicholasBlaskey]

Description

clearAgent state was broken. Add a test and fix it.

Test Plan

intg test

Commentary (optional)

Checklist

• Changes have been manually QA'd
• User-facing API changes need the "User-facing API Change" label.
• Release notes should be added as a separate file under docs/release-notes/.
  See Release Note for details.
• Licenses should be included for new code which was copied and/or modified from any external code.

Ticket

[netlify]

✅ Deploy Preview for determined-ui canceled.

Name	Link
🔨 Latest commit	a91d200
🔍 Latest deploy log	https://app.netlify.com/sites/determined-ui/deploys/65cbc9c1efd32c0007a11162

[codecov]

Codecov Report

Attention: 1 lines in your changes are missing coverage. Please review.

Comparison is base (393cfde) 47.68% compared to head (a91d200) 47.69%.
Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #8838      +/-   ##
==========================================
+ Coverage   47.68%   47.69%   +0.01%     
==========================================
  Files        1046     1065      +19     
  Lines      167950   169614    +1664     
  Branches     2240     2238       -2     
==========================================
+ Hits        80079    80901     +822     
- Misses      87713    88555     +842     
  Partials      158      158              

Flag	Coverage Δ
backend	43.47% <80.00%> (+0.28%)	⬆️
harness	64.11% <ø> (ø)
web	42.55% <ø> (ø)

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

Files	Coverage Δ
master/internal/rm/agentrm/agent_state.go	83.84% <80.00%> (-0.15%)	⬇️

... and 23 files with indirect coverage changes

[stoksc]

nice catch