GlobalDrupalSniff's use of $baseClasses is insufficient and fails to detect relevant cases

Problem/Motivation

Because GlobalDrupalSniff only checks the base class extended by the given class, it fails to detect a variety of instances where global Drupal calls are "bad." This might be a case where the base class simply isn't listed, such as any generic plugin that would extend PluginBase, or one that extends a class that extends one of the listed $baseClasses, or simply a generic service implementation that does not extend any other classes.

Steps to reproduce

Run DrupalPractice against any class that would go into /src/ that does not explicitly extend one of the classes listed in $baseClasses.

Proposed resolution

Replace the $baseClasses check with one that simply checks if this class's file resides in /src/, and add additional help text to the $warning to suggest that Plugins should implement ContainerFactoryPluginInterface.