Update Rspec to v3.12.0 & Jasmine to v3.99.0

[huwd]

What’s changed

Update rspec, minor version bump only

Identifying a user need

We need to keep our dependencies up to date, or this repo should be archived

[huwd]

Note Jasmine gem is End of Life.

The Jasmine Ruby gems are deprecated. There will be no further releases after                                                                                                                 
the end of the Jasmine 3.x series. We recommend that most users migrate to the                                                                                                                
jasmine-browser-runner npm package, which is the direct replacement for the                                                                                                                   
jasmine gem. See <https://jasmine.github.io/setup/browser.html> for setup                                                                                                                     
instructions, including for Rails applications that use either Sprockets or                                                                                                                   
Webpacker.                                                                                                                                                                                    
                                                                                                                                                                                              
If jasmine-browser-runner doesn't meet your needs, one of these might:                                                                                                                        
                                                                                                                                                                                              
* The jasmine npm package to run specs in Node.js:                                                                                                                                            
  <https://github.com/jasmine/jasmine-npm>                                                                                                                                                    
* The standalone distribution to run specs in browsers with no additional                                                                                                                     
  tools: <https://github.com/jasmine/jasmine#installation>                                                                                                                                    
* The jasmine-core npm package if all you need is the Jasmine assets:                                                                                                                         
  <https://github.com/jasmine/jasmine>. This is the direct equivalent of the                                                                                                                  
  jasmine-core Ruby gem.                                                                                                                                                                      

We should update this along with the readme. Separate PR however

[sengi]

Happened as part of #349 (and version constraints loosened to pin just the major, so should be less update toil in future).