added certificate chain verification

[johnabass]

I think this will verify that peer certs are in the root CA chain, which is what's installed locally.

[codecov]

Codecov Report

Attention: Patch coverage is 66.66667% with 5 lines in your changes missing coverage. Please review.

Project coverage is 55.33%. Comparing base (b48cdb2) to head (e0c50d5).
Report is 2 commits behind head on main.

Files with missing lines	Patch %	Lines
token/claimBuilder.go	66.66%	4 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #254      +/-   ##
==========================================
+ Coverage   55.25%   55.33%   +0.07%     
==========================================
  Files          54       54              
  Lines        2320     2335      +15     
==========================================
+ Hits         1282     1292      +10     
- Misses       1011     1015       +4     
- Partials       27       28       +1     

Flag	Coverage Δ
unittests	55.33% <66.66%> (+0.07%)	⬆️

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.