fix: Improves activity type for the site to close #63.

src/transformer/utils/get_activity/site.php

...course_module_viewed/viewing_scorm_module/statements.json

...urse_completed/completing_existing_course/statements.json

...ore/course_viewed/viewing_existing_course/statements.json

...s/core/user_created/existing_user_created/statements.json

..._enrolment_created/existing_user_enrolled/statements.json

...core/user_loggedin/existing_user_loggedin/statements.json

...re/user_loggedout/existing_user_loggedout/statements.json

...ignment_graded/existing_assignment_graded/statements.json

...t_submitted/existing_assignment_submitted/statements.json

...cancel_booking/existing_booking_cancelled/statements.json

...ce/signup_success/existing_signup_success/statements.json

...take_attendance/existing_attendance_taken/statements.json

...back/response_submitted/existing_response/statements.json

...cussion_viewed/existing_discussion_viewed/statements.json

...user_report_viewed/existing_report_viewed/statements.json

...ttempt_reviewed/existing_attempt_reviewed/statements.json

.../attempt_started/existing_attempt_started/statements.json

...empt_submitted/existing_attempt_submitted/statements.json

..._scorm/sco_launched/existing_sco_launched/statements.json