Resolve "Overview: Replace the course link with a button on the overview"

What does this mr do?

Adds a view course button instead of clicking on the course name, this way enrolling and viewing a course look the same and it is more intuitive. Also cleaned up the thyme leaf template by removing redundant code.

Screenshots

after

Does this MR meet the acceptance criteria?

• I have added a changelog entry to reflect the significant changes I made.
• Tests were created to test the feature.
• I have updated the documentation accordingly.
• I adhere to the style guide.

Closes #121 (closed)