Does not update lessons content when dynamic page cache is enabled

Problem/Motivation

Functional tests have a problem that node (lesson) isn't updating after editing. That happens only after clearing the cache. Everything looks fine doing the same but on real site (not via the tests).

Steps to reproduce

1. Write any Functional test
2. Add a node
3. Edit that node and hit save
4. No updates on the page before clearing the cache

Proposed resolution

Check what is a problem and decide what is the better way to resolve it.

Remaining tasks

User interface changes

API changes

Data model changes