Add note about entity reference purger

[rosiel]

Purpose / why

Thanks @kayakr in Slack! Found the module I was tempted to make.

What changes were made?

• described Entity Reference Purger
• listed some warnings of when you might not want to use it

Verification

Particulary if @kayakr knows some of these things!

Interested Parties

• @Islandora/documentation
• @Islandora/committers

Checklist

Pull-request Reviewer

Pull-request reviewer should ensure the following:

• Does this PR link to related issues?
• Does the proposed documentation align with the Islandora Documentation Style Guide?
• Are the changes accurate, useful, free of typos, etc?

Person Merging

The person merging should ensure the following:

• Does mkdocs still build successfully? (This is indicated by TravisCI passing. To test locally, and see warnings, see How To Build Documentation.)
• If pages are renamed or removed, have all internal links to those pages been fixed?
• If pages are added, have they been linked to or placed in the menu?
• Did the PR receive at least one approval from a committer, and all issues raised have been addressed?

[github-actions]

PR Preview Action v1.4.7
Preview removed because the pull request was closed.
2024-08-28 17:21 UTC

[seth-shaw-asu]

👍