Add FutureWarning to SumTo1 transform deprecation

[hshah06]

Description

Related Issue

• Closes Deprecate SumTo1 Transform #7009
• Related to #

Checklist

• Checked that the pre-commit linting/style checks pass
• Included tests that prove the fix is effective or that the new feature works
• Added necessary documentation (docstrings and/or example notebooks)
• If you are a pro: each commit corresponds to a relevant logical change

Type of change

• New feature / enhancement
• Bug fix
• Documentation
• Maintenance
• Other (please specify):

Added a FutureWarning to the SumTo1 transform to notify users it is deprecated
and will be removed in a future version, pointing them to use the Simplex
transform instead. Also added a test to verify the warning is raised on instantiation.

[read-the-docs-community]

Documentation build overview

📚 pymc | 🛠️ Build #31849751 | 📁 Comparing f24eed6 against latest (6c48a0b)

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Show files changed (15 files in total): 📝 15 modified | ➕ 0 added | ➖ 0 deleted

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glossary.html	📝 modified
api/generated/pymc.draw.html	📝 modified
api/generated/pymc.icdf.html	📝 modified
api/generated/pymc.logcdf.html	📝 modified
api/generated/pymc.logp.html	📝 modified
api/generated/pymc.sample_posterior_predictive.html	📝 modified
api/generated/pymc.sample_prior_predictive.html	📝 modified
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api/distributions/generated/classmethods/pymc.SymbolicRandomVariable.update.html	📝 modified
api/model/generated/classmethods/pymc.model.core.Model.compile_fn.html	📝 modified