Resolve "Average waiting time distribution in a lab"

What does this mr do?

• Adds a graph
• Changes the way we calculate average times for waiting and processing in EditionStatusService to consider active requests.

Screenshots

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 #589 (closed)