Add sorting for grading

[thortol]

Description

To be merged with Frontend #2893

For implementation decisions, see Frontend PR.

Changes

• Changed submissions_by_grader_for_index pipeline by adding user table, assessment.title and assessment.config_id
• Added sort_submission to sort the query in the pipeline

Type of change

• [ ] Bug fix (non-breaking change which fixes an issue)
• [x] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to not work as expected)
• [ ] This change requires a documentation update
• [ ] Code quality improvements

Checklist

• [x] I have tested this code
• [ ] I have updated the documentation

[coveralls]

coverage: 94.378% (-0.3%) from 94.68% when pulling 842cef1bca5024e5e92aa7422413777e6eca363c on thortol:add-sorting-for-grading into 76cb9f71705eae9f74d3a83fe461eff244326b19 on source-academy:master.

[RichDom2185]

Is this PR ready?

[RichDom2185]

Sorry for the delayed review…