Add mononym support

[damianhxy]

Description

Initial attempt to add mononym support, by updating user validation to only require at least one of first_name and last_name.

Pages with style changes for mononyms

• Assessment Gradesheet
• Course view student CUD
• Assessment Manage submissions
• User Account
• Assessment Scoreboard
• Course Metrics Watchlist
• Assessment Gradesheet grader information
• (course_user_data index and user pages -- they seemed unused as show is used instead)

A good litmus test is to run grep -nr "\.first_name.*\.last_name" . and look at the results

Other changes

• Use flash.now for roster update success flash as otherwise the flash persists for one additional page load
• Update user.rb#full_name method to handle mononyms
• Update user.rb#display_name method to correctly use .present? to check for presence, since empty strings are truthy. Note: this method seems pretty redundant, and is mainly used in the navbar and Account page; we could probably delete this method and use full_name directly instead

Motivation and Context

To support students who do not have first names or last names.

Fixes #1536

How Has This Been Tested?

Import roster containing mononyms

Supports Mononyms

Correctly validates against completely blank names

Check miscellaneous styling

Gradesheet

View student CUD

Manage submissions

Account

Scoreboard

Watchlist

Grader information

Also, check that various functionality such as sudo, extensions, create submissions still work

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• I have run rubocop for style check. If you haven't, run overcommit --install && overcommit --sign to use pre-commit hook for linting
• My change requires a change to the documentation, which is located at Autolab Docs
• I have updated the documentation accordingly, included in this PR

[20wildmanj]

For the most part, everything seems to work!

Checked:

• import course roster
• watchlist
• course user data
• grading as a CA with mononym and verifying grader info is correct
• gradesheet and submissions
• extensions
• scoreboard
• submitting assessments
• creating user through "Add User to Course"
• creating annotations

[20wildmanj]

I couldn't test annotations fully however because it seems like as a student, I am having difficulties getting annotations to appear, because I get an authentication error. When I look at a submission, the annotations don't appear and I get this:

This doesn't seem limited to just this branch however, seems like it also occurs on master. I don't know how to check this on autolab-dev/nightly because I don't know a student user I can log into, and I get a 500 error if I try to create a user.

[damianhxy]

I couldn't test annotations fully however because it seems like as a student, I am having difficulties getting annotations to appear, because I get an authentication error. When I look at a submission, the annotations don't appear and I get this

As discussed offline, it seems that the grading deadline must pass before annotations will be available to students, even if grades are already released. Whether this is intended behavior is up for debate.

The error seen in the console is unrelated. Rather, we are polling the shared comments endpoint even for students, which naturally leads to an authentication error. The same can be observed for the metrics watchlist endpoint on the view course page.

Ideally, we should avoid polling these endpoints for students, but it's not a big deal.