Hi, Dima. I assume you are refering to ch 03 taco-jpa module of the book.
Can you try to update the pom.xml of taco-jpa and see if it works without changing any original code?
Please refer to the bold type of the following pom.xml.
Also, if you are using IntelliJ, make sure your project setting's compiler is set to JDK 11 if you are using it.