Fix application of custom isotopics to work with Fluid classes

[keckler]

What is the change?

There was a bug in components that combined custom isotopics with material classes that are instances of Fluid. In those cases, the density was not being adjusted from Tinput -> Thot when the component was initialized.

See #2070 for more details.

Why is the change being made?

Fix a bug (#2070 )

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Checklist

• This PR has only one purpose or idea.
• Tests have been added/updated to verify any new/changed code.

• The code style follows good practices.
• The commit message(s) follow good practices.

• The release notes have been updated if necessary.
• The documentation is still up-to-date in the doc folder.
• The dependencies are still up-to-date in pyproject.toml.

[keckler]

While this has a unit test, I am running some cases offline to be extra sure.

[keckler]

Okay, pretty sure this is ready to go. Let me know if there are any questions.

[bsculac]

Looks good, I think these changes fall under what is currently documented so no additional documentation is necessary.

[john-science]

Have you run downstream tests for this repo? (Expect me to ask that question for all your current bug fix PRs today. lawls)

[john-science]

I think this should have a release note under "Bug Fixes".

[john-science]

Looks good.

Could use a release note.

[keckler]

Have you run downstream tests for this repo? (Expect me to ask that question for all your current bug fix PRs today. lawls)

Yes I have. I came upon this bug because I was playing around with our model of JOYO and was getting some incorrect answers. After this PR, the model appears to be working appropriately, and the predictions line up very well with experiment.

[keckler]

Looks good.

Could use a release note.

Done!