feature/manual refresh on challenge page(s) & leaderboard

[koreangeekman]

Is your feature request related to a problem? Please describe.
Would like ability to refresh the data without refreshing the page

Describe the solution you'd like
Manual refresh button either for the entire challenge & leaderboard pages or a button on each sub-page

Describe alternatives you've considered
onMounted re-get of the relative data for each subpage..

Additional context
remove the currently implemented onMounted on the "Grade Users" subpage if a button is implemented

[koreangeekman]

Potential placements for a manual refresh:

Challenges - Browse page

Leaderboard

Challenge page:

• Statistics
• Submissions
• Grading
• Moderators

May also create manual refresh for all in a DevFlag but only enable for specific spots..