This project was created to reproduce the bug in spring-data-jdbc when we try to load only one column from a table inside
an Optional, and its value is null in DB, it is throwing Couldn't find PersistentEntity for type class java.lang.String!
exception (because in this example I am returning an String inside the Optional).
This behavior has started after upgrading spring-boot from 2.5.10 to 2.6.0
To reproduce the error, run all tests with the command
./gradlew cleanTest test -i