Introduce some metric functions

[ytdHuang]

Checklist

Thank you for contributing to QuantumToolbox.jl! Please make sure you have finished the following tasks before opening the PR.

• Please read Contributing to Quantum Toolbox in Julia.
• Any code changes were done in a way that does not break public API.
• Appropriate tests were added and tested locally by running: make test.
• Any code changes should be julia formatted by running: make format.
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• (If necessary) the CHANGELOG.md should be updated (regarding to the code changes) and built by running: make changelog.

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Description

This PR implements the following metric functions:

• hilbert_dist
• hellinger_dist
• bures_dist
• bures_angle

Related issues or PRs

close #414

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 94.33%. Comparing base (71b8d8c) to head (dc6454f).
Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #420      +/-   ##
==========================================
+ Coverage   94.31%   94.33%   +0.01%     
==========================================
  Files          47       47              
  Lines        2953     2963      +10     
==========================================
+ Hits         2785     2795      +10     
  Misses        168      168              

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