Fix: state: circsuypply calc around null blocks

[arajasek]

Related Issues

Bug introduced in #7811

Proposed Changes

Additional Info

Checklist

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• All commits have a clear commit message.
• The PR title is in the form of of <PR type>: <#issue number> <area>: <change being made>
  • example: fix: #1234 mempool: Introduce a cache for valid signatures
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• This PR has tests for new functionality or change in behaviour
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• CI is green

[arajasek]

Need for a test is well demonstrated, to come :P