Release: 2.0.0-beta.4

[crvernon]

This pull request removes several documentation files and updates the documentation index to eliminate references to these files. The primary goal is to clean up the documentation by removing detailed how-to guides, demos, and the common issues section.

The most important changes are:

Documentation Removal:

• Deleted the following how-to and demo documentation files: cache_hash.rst, container.rst, helps_demo.rst, and issues.rst, removing guidance on custom hashing, container setup, a HELPS demo, and common issues. [1] [2] [3] [4]

Index Update:

• Updated index.rst to remove the "How-tos", "Demos", and "Common Issues" toctree sections, reflecting the removal of the associated documentation files.