Display kwargs on show job page

[zubin]

Context

• Show job's kwargs column (for Ruby 3 / Que 2 jobs) #105

Job args are displayed on the show and list pages, but not kwargs.

When debugging failed jobs with kwargs, it is critical to have this information.

Change

• Add kwargs to the show job page.

Discussion

• I considered also adding kwargs to the list pages but it pushed the table too wide.
• There doesn't appear to be test coverage for this part of the code, so I didn't add any. I did test it manually though.