feat(tests): Opcode tests: stack overflow & BLOCKHASH

[pdobacz]

🗒️ Description

Two additions:

1. It seems there weren't tests covering stack overflow for some opcodes
2. Other one is an addition to the existing BLOCKHASH test, which didn't cover the situation where the instruction attempts to read beyond the 256 recent blocks. Catch here is that it comes up as MC/DC coverage gap even after it is filled. But I validated manually modifying the code - removing the decision's condition does indeed cause the new tests to fail. Not sure why would the report got this wrong.

🔗 Related Issues or PRs

N/A.

✅ Checklist

• All: Ran fast tox checks to avoid unnecessary CI fails, see also Code Standards and Enabling Pre-commit Checks:

  uvx tox -e static

• All: PR title adheres to the repo standard - it will be used as the squash commit message and should start type(scope):.
• All: Considered adding an entry to CHANGELOG.md.
• All: Set appropriate labels for the changes (only maintainers can apply labels).

[codecov-commenter]

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Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 86.07%. Comparing base (9563a51) to head (14b1585).
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Additional details and impacted files

@@             Coverage Diff              @@
##           forks/osaka    #1728   +/-   ##
============================================
  Coverage        86.07%   86.07%           
============================================
  Files              743      743           
  Lines            44078    44078           
  Branches          3894     3894           
============================================
  Hits             37938    37938           
  Misses            5659     5659           
  Partials           481      481           

Flag	Coverage Δ
unittests	86.07% <ø> (ø)

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[LouisTsai-Csie]

Thanks for the PR, leave some suggestion!

[LouisTsai-Csie]

I like this approach!