Bump kokkos versions.

[vincentmr]

Before submitting

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• All new features must include a unit test.
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---

Context:
Kokkos has a mix of 4.0.01 and 4.1.00 among the CMake files, CI, etc.

Description of the Change:
Use Kokkos 4.2.00 (latest) everywhere.

Benefits:
Up-to-date Kokkos and uniformized version.

Possible Drawbacks:

Related GitHub Issues:

[github-actions]

Hello. You may have forgotten to update the changelog!
Please edit .github/CHANGELOG.md with:

• A one-to-two sentence description of the change. You may include a small working example for new features.
• A link back to this PR.
• Your name (or GitHub username) in the contributors section.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (4290e60) 98.68% compared to head (1271f2b) 98.68%.

Additional details and impacted files

@@           Coverage Diff           @@
##           master     #578   +/-   ##
=======================================
  Coverage   98.68%   98.68%           
=======================================
  Files         167      167           
  Lines       23959    23959           
=======================================
  Hits        23644    23644           
  Misses        315      315           

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