Non-existing class usage

[volodymyrdovhan]

Hello,
I found non-existing class usage in the code. Please review:

[francopantoja]

Hi

The non-existing class has been deleted in the code

[elena3ip]

This class exists in Moodle 4.1. This plugin is only valid for this moodle version.

[juacas]

Related to #73
What solution is proposed? Manage in branch MOODLE_STABLE405?