Upgrade Ruby, Rails and various gems

[peter-hank]

https://cyber.harvard.edu/projectmanagement/issues/16955
https://cyber.harvard.edu/projectmanagement/issues/16956

[peter-hank]

Still on Rails 5.2.0 because of rzane/baby_squeel#97.

[peter-hank]

@jdcc can you take a look?

I haven't tried to test any rake tasks, I'm not sure if any of them is still in use, if so, let me know.

[peter-hank]

We will need to reindex the search index.

[jdcc]

The oai repo changes are on the master branch now, so that branch spec can go.

I'm having an issue getting this running. When I run bundle install, I get this:

You have requested:                                                
  rails = 5.2.3                                                            
                                                           
The bundle currently has rails locked at 5.2.0.
Try running `bundle update rails`

Do you see this if you try to update from the current dev, or is this a me issue?

[peter-hank]

@jdcc

Yeah, my bad, incidently pushed the 5.2.3 Gemfile version. You can try again.

[peter-hank]

I've tested it with PostgreSQL 12.0 and can't really see any issues. I've just exported the database from 9.3 and imported in 12. Hopefully we don't need anything else.

[jdcc]

Looks good. I'll write up directions and have it deployed to QA.