Imaginary part displayed on plot_hinton in Visualization

[dimple12M]

Fixes #8324

Issue in the Imaginary section of the plot_hinton. matrix elements displayed not properly and the square size in the imaginary part were not equal.
In the image below, the imaginary part of the plot_hinton has 2 issues:

1. imaginary matrix elements not displayed properly
2. squares in the img are not equal.
   

In the Image below, done few changes in the state_visualization.py and the following correct plot is observed.

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[1ucian0]

Hi @dimple12M, this PR looks... a bit... unorthodox :)

DEV recently released a very nice article and short article that explains how to do open-source contributions. Have a look, specifically to the Pull Requests section. You can also ask for help in the #qiskit-pr-help channel in Slack.

[dimple12M]

Hi ,
With respect to this query https://qiskit.slack.com/archives/CB6C24TPB/p1657185479453929 I made few changes in the state_visualization.py file . This is my first PR related to the Qiskit source code contribution. I understand there are some guidelines to follow. But I am unable to get it about whether this issue is valid and can I do the PR again ?
Kindly, request to get some info related to this.