[WIP] Upgrade to Ruby 3.3

[mayorova]

This was an experiment to see whether it could replace #3847 easily, but it turned out to be more effort than I was hoping for...

Some of the errors I saw and tried to fix:

/home/dmayorov/.asdf/installs/ruby/3.3.1/lib/ruby/gems/3.3.0/gems/css_parser-1.12.0/lib/css_parser/regexps.rb:11:in `initialize': wrong number of arguments (given 3, expected 1..2) (ArgumentError)

  RE_NON_ASCII = Regexp.new('([\x00-\xFF])', Regexp::IGNORECASE, 'n') # [^\0-\177]
                            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
	from /home/dmayorov/.asdf/installs/ruby/3.3.1/lib/ruby/gems/3.3.0/gems/css_parser-1.12.0/lib/css_parser/regexps.rb:11:in `new'

The fix is to upgrade css_parser to version 1.15.0 or higher: https://github.com/premailer/css_parser/blob/4fc5b070fb13f739eadbb27a4c5957f1713f12c6/CHANGELOG.md?plain=1#L27

---

/home/dmayorov/.asdf/installs/ruby/3.3.1/lib/ruby/gems/3.3.0/gems/compass-1.0.3/lib/compass/configuration/helpers.rb:89:in `block in detect_configuration_file': undefined method `exists?' for class File (NoMethodError)

        possible_files.detect{|f| File.exists?(f)}
                                      ^^^^^^^^
Did you mean?  exist?
	from /home/dmayorov/.asdf/installs/ruby/3.3.1/lib/ruby/gems/3.3.0/gems/compass-1.0.3/lib/compass/configuration/helpers.rb:89:in `each'

It's reported here but looks like it doesn't have a fix.
The reason is that File.exists? was removed in Ruby 3.2, now only File.exist? is available: https://www.ruby-lang.org/en/news/2022/12/25/ruby-3-2-0-released/

The workaround (althout ugly) I applied was

File.class_eval do
  class << self
    alias_method :exists?, :exist?
  end
end

---

/home/dmayorov/.asdf/installs/ruby/3.3.1/lib/ruby/gems/3.3.0/gems/pry-0.13.1/lib/pry/code.rb:342:in `<class:Code>': undefined method `=~' for class `Pry::Code' (NameError)
	from /home/dmayorov/.asdf/installs/ruby/3.3.1/lib/ruby/gems/3.3.0/gems/pry-0.13.1/lib/pry/code.rb:32:in `<class:Pry>'

Related issue: https://gitlab.com/gitlab-org/customers-gitlab-com/-/issues/6143

Solved by upgrading pry dependencies: bundle update pry-shell pry-byebug pry

---

Then finally the server started and the admin portal apparently was working, but on trying to load the dev portal:

NoMethodError (undefined method `tainted?' for an instance of String):
  
lib/developer_portal/lib/liquid/xss_protection.rb:15:in `render'

Related issues:
Shopify/liquid#1625
Shopify/liquid#1268

The solution is to upgrade liquid to 5.0.0. But it caused another issue:

/home/dmayorov/Projects/3scale/porta/lib/developer_portal/config/initializers/liquid.rb:5:in `<main>': can't modify frozen Hash: {nil=>nil, "nil"=>nil, "null"=>nil, ""=>nil, "true"=>true, "false"=>false, "blank"=>"", "empty"=>""} (FrozenError)
	from /home/dmayorov/.asdf/installs/ruby/3.3.1/lib/ruby/gems/3.3.0/gems/activesupport-6.1.7.8/lib/active_support/dependencies.rb:326:in `load'
	from /home/dmayorov/.asdf/installs/ruby/3.3.1/lib/ruby/gems/3.3.0/gems/activesupport-6.1.7.8/lib/active_support/dependencies.rb:326:in `block in load'

This is where I decided to stop 🙃 We'll upgrade in another step.