Entity queries must explicitly set whether the query should be access checked or not

Problem/Motivation

Following a deprecation as of Drupal 9.2, Drupal 10 enforces that entity queries must specify an accessCheck, throwing an exception otherwise. In the module's current state (along with the automated patch provided in #3296961 that makes it otherwise D10-compatible), digests fail to send because the entity queries in the module don't include them.

Steps to reproduce

Use the module on a Drupal 10 site. Run a cron job that triggers digest_cron(). An error will appear in the logs, and the digest will have failed to send.

Proposed resolution

Add accessCheck()s to any entity queries throughout the module.

Patch forthcoming.