Remove redundant Qmat, Amat calls from generate_hafnian_sample

[thonic]

Context:
There is an extra call of the Qmat function in the generate_hafnian_sample function.

Description of the Change:
Remove redundant call of Qmat, Amat from generate_hafnian_sample.

Benefits:
Removed redundant code

Possible Drawbacks:
None

Related GitHub Issues:
None

[codecov]

Codecov Report

Merging #343 (16c018b) into master (d15656c) will not change coverage.
The diff coverage is n/a.

@@            Coverage Diff            @@
##            master      #343   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files           24        24           
  Lines         1726      1725    -1     
=========================================
- Hits          1726      1725    -1     

Impacted Files	Coverage Δ
thewalrus/samples.py	100.00% <ø> (ø)

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[thisac]

Thanks for the contribution @thonic! Great find! I only had a few minor comments that would be good to address. Let me know if you have any questions about them.

[thonic]

@thisac I agree with all the comments, I have changed the commits accordingly, thank you.

[thonic]

@sduquemesa done

[thisac]

Looks great! Thanks for the contribution @thonic!