Update for Chef 17

[b-dean]

Work in progress to get some of this stuff working on Chef 17.

• Use Ruby 3.0.0
• Use newer Minitest gem Probably not this. The newer minitest is pretty incompatible with minitest-chef-handler gem and I don't want to fix that.
• Use cookstyle instead of foodcritic and newer versions of various other gems

Also fixes the gem update stuff that's in these dependabot PRs:

• Bump rubyzip from 1.2.1 to 1.3.0 #80
• Bump ffi from 1.9.18 to 1.11.1 #82
• Bump yajl-ruby from 1.3.0 to 1.4.1 #83
• Bump rubocop from 0.34.2 to 0.48.1 #85
• Bump excon from 0.55.0 to 0.71.0 #86
• Bump rake from 12.0.0 to 12.3.3 #89
• Bump rack from 2.0.1 to 2.2.3 #90
• Bump json from 1.8.6 to 2.3.1 #91
• Bump nokogiri from 1.7.1 to 1.11.4 #92

[b-dean]

@btm, the change to require Chef 14+ as well as switching the gem to be defined in metadata.rb probably should make this go to 2.0.0.

If you don't want that I can split this into two PRs, one with the Chef 14+ breaking change stuff, and one with the hack to get RSpec/Inspec to stop messing with minitest.