Use get_course_by_id to fix RED-3118

Change description

Since the template lms/templates/dashboard/_dashboard_course_listing.html is using enrollment variable that is already checked by get_course_with_access then we can safely call get_course_by_id instead in this template. This is to resolve the redirect issue in RED-3118

Type of change

[x] Bug fix (fixes an issue)
[ ] New feature (adds functionality)

Checklists

Development

[ ] Lint rules pass locally
[ ] Application changes have been tested thoroughly
[ ] Automated tests covering modified code pass

Security

[ ] Security impact of change has been considered
[ ] Code follows company security practices and guidelines

Code review

[ ] Pull request has a descriptive title and context useful to a reviewer. Screenshots or screencasts are attached as necessary
[ ] "Ready for review" label attached and reviewers assigned
[ ] Changes have been reviewed by at least one other contributor
[ ] Pull request linked to task tracker where applicable

appsembler / edx-theme-customers

Use get_course_by_id to fix RED-3118 #214