Update citation and add missing publications

[RemDelaporteMathurin]

Proposed changes

This PR just updates the preferred citation and add missing publications to the docs.

Types of changes

What types of changes does your code introduce to FESTIM?

• Bugfix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Code refactoring
• Documentation Update (if none of the other choices apply)
• New tests

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 99.48%. Comparing base (b5035d6) to head (4e1d9d0).

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #717   +/-   ##
=======================================
  Coverage   99.48%   99.48%           
=======================================
  Files          58       58           
  Lines        2350     2350           
=======================================
  Hits         2338     2338           
  Misses         12       12           

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[jhdark]

Great to get this in too