Steps to reproduce:

• Create a course (Course 1)
• Create a user tour with the following settings:
  • Name - Welcome to Course 1
  • Apply to URL match - leave this blank
  • Tour is enabled - checked
  • Tour filters: Courses - Course 1
  • All other settings should be left as default
• Add a new step to the tour, with the following settings:
  • Target type: Display in the middle of page
  • Title: Welcome
  • Content: Welcome to Course 1
• Make sure the tour is the first one on the list, so no other tour will be chosen instead
• Login as the user who is not enrolled on Course 1 (and cannot view it without enrolment)
• Try to visit Course 1
• You will then be redirected to the enrolment page

Expected outcome:

• Moodle makes no attempt to launch the user tour, as the user does not have permission to access the course

Actual outcome:

• Moodle attempts to display the tour, but fails and shows a 'requireloginerror' popup

Error stack trace:
Not enrolled
Error code: requireloginerror

• line 2943 of /lib/moodlelib.php: require_login_exception thrown
• line 498 of /lib/externallib.php: call to require_login()
• line 62 of /admin/tool/usertours/classes/external/tour.php: call to external_api::validate_context()
• line 244 of /lib/externallib.php: call to tool_usertours\external\tour::fetch_and_start_tour()
• line 59 of /lib/ajax/service.php: call to external_api::call_external_function()