GibbsComputedStructureEntry update to handle float temperature values

[slee-lab]

Summary

Issue: when temperature %100==0 but is type float, you get KeyError because G_ELEMS has keys of integer values.

Major changes:

• feature 1: updated to handle float temperature values
• fix 1: G_ELEMS[str(self.temp)] is changed to G_ELEMS[str(int(self.temp))]

Checklist

• Google format doc strings added. Check with ruff.
• Type annotations included. Check with mypy.
• Tests added for new features/fixes.
• If applicable, new classes/functions/modules have duecredit @due.dcite decorators to reference relevant papers by DOI (example)

Tip: Install pre-commit hooks to auto-check types and linting before every commit:

pip install -U pre-commit
pre-commit install