Feat: add clamped Pockels calculation capability

[vdemestral]

I add the possibility of computing the clamped Pockels tensors into the VibroMixing class.

[cla-bot]

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[cla-bot]

Thank you for your pull request and welcome to our community. We could not parse the GitHub identity of the following contributors: Virginie de Mestral.
This is most likely caused by a git client misconfiguration; please make sure to:

1. check if your git client is configured with an email to sign commits git config --list | grep email
2. If not, set it up using git config --global user.email email@example.com
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[cla-bot]

Thank you for your pull request and welcome to our community. We could not parse the GitHub identity of the following contributors: Virginie de Mestral.
This is most likely caused by a git client misconfiguration; please make sure to:

1. check if your git client is configured with an email to sign commits git config --list | grep email
2. If not, set it up using git config --global user.email email@example.com
3. Make sure that the git commit email is configured in your GitHub account settings, see https://github.com/settings/emails

[bastonero]

The code is awesome, thanks @vdemestral ! Just some minor changes!

[aiida-cla-bot]

All contributors have accepted the CLA ✅

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[vdemestral]

I have read the CLA Document and I hereby accept the CLA

[bastonero]

recheck

[codecov]

Codecov Report

Attention: Patch coverage is 70.21277% with 14 lines in your changes missing coverage. Please review.

Project coverage is 86.45%. Comparing base (81367a0) to head (50b5a34).

Files with missing lines	Patch %	Lines
src/aiida_vibroscopy/data/vibro_mixin.py	14.28%	12 Missing ⚠️
src/aiida_vibroscopy/calculations/spectra_utils.py	93.93%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main      #67      +/-   ##
==========================================
- Coverage   86.77%   86.45%   -0.32%     
==========================================
  Files          34       34              
  Lines        2502     2548      +46     
==========================================
+ Hits         2171     2203      +32     
- Misses        331      345      +14     

Flag	Coverage Δ
pytests	86.45% <70.21%> (-0.32%)	⬇️

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[vdemestral]

I have read the CLA Document and I hereby accept the CLA