validating certificate template subjectname fleet vars

[ksykulev]

Related issue: Resolves #36289

Testing

• Added/updated automated tests
• QA'd all new/changed functionality manually

[codecov]

Codecov Report

❌ Patch coverage is 64.10256% with 14 lines in your changes missing coverage. Please review.
✅ Project coverage is 66.00%. Comparing base (300c263) to head (0b0cd03).
⚠️ Report is 11 commits behind head on main.

Files with missing lines	Patch %	Lines
server/service/certificate_templates.go	77.77%	3 Missing and 3 partials ⚠️
server/service/client.go	0.00%	3 Missing and 1 partial ⚠️
server/datastore/mysql/teams.go	50.00%	1 Missing and 1 partial ⚠️
server/service/certificates.go	50.00%	2 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff            @@
##             main   #36377    +/-   ##
========================================
  Coverage   65.99%   66.00%            
========================================
  Files        2136     2134     -2     
  Lines      182057   181875   -182     
  Branches     7594     7540    -54     
========================================
- Hits       120155   120041   -114     
+ Misses      50913    50840    -73     
- Partials    10989    10994     +5     

Flag	Coverage Δ
backend	67.58% <64.10%> (-0.01%)	⬇️

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[juan-fdz-hawa]

I might be missing something here, but isn't a similar pattern matching logic already implemented into variables.Find(...)? Why is this required?

[ksykulev]

Oh! I did not realize variables.Find already did this! Great! thank you.

[juan-fdz-hawa]

Failed tests seem not to be related to the PR