simulator: fix region size and keys

[lhy1024]

What problem does this PR solve?

Issue Number: Ref #8135

What is changed and how does it work?

Check List

Tests

• Unit test

Release note

None.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 77.23%. Comparing base (bc28a0f) to head (ed9f9f2).

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #8366      +/-   ##
==========================================
+ Coverage   77.22%   77.23%   +0.01%     
==========================================
  Files         470      470              
  Lines       61681    61681              
==========================================
+ Hits        47634    47641       +7     
+ Misses      10471    10453      -18     
- Partials     3576     3587      +11     

Flag	Coverage Δ
unittests	77.23% <ø> (+0.01%)	⬆️

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[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: HuSharp, rleungx

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• OWNERS [HuSharp,rleungx]

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[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2024-07-05 02:23:24.725753111 +0000 UTC m=+1550331.211241936: ☑️ agreed by HuSharp.
• 2024-07-05 03:24:50.794049707 +0000 UTC m=+1554017.279538538: ☑️ agreed by rleungx.