Support all entity types

Problem/Motivation

In #3534094 💬 Create new entity reference Active , I posted my initial experience with the module, with confusing from seeing "Terms" in the UI instead of "Entities".

Steps to reproduce

Configure a field and look at the options.

Proposed resolution

Does this module support non-taxonomy entities?
If so, can we change the UI text to say "Entities"?
If not, can we get it working?

Remaining tasks

• ✅ File an issue
• ➖ Addition/Change/Update/Fix
• ➖ Testing to ensure no regression
• ➖ Automated unit testing coverage
• ➖ Automated functional testing coverage
• ➖ UX/UI designer responsibilities
• ➖ Readability
• ➖ Accessibility
• ➖ Performance
• ➖ Security
• ➖ Documentation
• ➖ Code review by maintainers
• ➖ Full testing and approval
• ➖ Credit contributors
• ➖ Review with the product owner
• ➖ Release notes snippet
• ❌ Release

API changes

• N/A

Data model changes

• N/A

Release notes snippet

• N/A