Fixed #600 Assert against non-sensible excluded_accounts

[smoy]

What changed?

• Assert against non-sensible excluded_accounts

Rationale

• During import phase, we don't want to generate non-sensible excluded_accounts. If it's a new template, import logic does not know how to generate exclude_accounts. If there is an existing template, the best it can do if old template doesn't have exclude_account, it shouldn't add new excluded_accounts.

How was it tested?

If it was manually verified, list the instructions for your reviewers to follow.

• Unit Tests
• Functional Tests
• Manually Verified

Relying existing test suite.

[castrapel]

LGTM

[codecov]

Codecov Report

❌ Patch coverage is 33.33333% with 8 lines in your changes missing coverage. Please review.
✅ Project coverage is 73.27%. Comparing base (e3f5f0c) to head (3c5ed76).
⚠️ Report is 186 commits behind head on main.

Files with missing lines	Patch %	Lines
iambic/core/template_generation.py	33.33%	8 Missing ⚠️

❌ Your patch check has failed because the patch coverage (33.33%) is below the target coverage (75.00%). You can increase the patch coverage or adjust the target coverage.
❌ Your project check has failed because the head coverage (73.27%) is below the target coverage (75.00%). You can increase the head coverage or adjust the target coverage.

❗ There is a different number of reports uploaded between BASE (e3f5f0c) and HEAD (3c5ed76). Click for more details.

HEAD has 2 uploads less than BASE

Flag	BASE (e3f5f0c)	HEAD (3c5ed76)
functional_tests	1	0
functional_tests_config_discovery	1	0

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #601      +/-   ##
==========================================
- Coverage   83.01%   73.27%   -9.75%     
==========================================
  Files         105      105              
  Lines       12549    12560      +11     
==========================================
- Hits        10418     9203    -1215     
- Misses       2131     3357    +1226     

Flag	Coverage Δ
functional_tests	?
functional_tests_config_discovery	?
unit_tests	73.27% <33.33%> (-0.05%)	⬇️

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