Add assertion for number of qubits in Circuit init

[Shiro-Raven]

No description provided.

[codecov]

Codecov Report

Merging #425 (d8d5318) into dev (f53a327) will increase coverage by 0.01%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##              dev     #425      +/-   ##
==========================================
+ Coverage   90.88%   90.89%   +0.01%     
==========================================
  Files          63       63              
  Lines        3564     3571       +7     
  Branches      571      574       +3     
==========================================
+ Hits         3239     3246       +7     
  Misses        217      217              
  Partials      108      108              

Impacted Files	Coverage Δ
src/python/zquantum/core/circuits/_circuit.py	90.14% <100.00%> (+1.07%)	⬆️

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[dexter2206]

I think we have an unused import in _circuit.py, otherwise looks good!