Put the internal utility functions in another file

Problem/Motivation

In the .module file, there are some functions that only are important to the module (and not for others) that not are hook implementations, this functions should be in another file as they are Utility functions that can be used on other files inside the module. You can find more about this in Where to place the utility and internal functions for a custom module?

Proposed resolution

Create the InternalFunctions class inside the Drupal\MODULE_NAME\Utility namespace and put inside all the module internal functions that not are hooks implementations.

Remaining tasks

None.

User interface changes

None.

API changes

None.

Data model changes

None.