**BREAKING**: Drop support for ruby 2.4

* Upgrade rubocop to version 1.22.0
* InvalidPredicateMatcher and CustomIncludeMethods are removed
* Add dependencies on `rubocop-rails` and `rubocop-performance`

Thanks @bmulholland and @RenzoMinelli

Follow up rubocop/rubocop#8365.

This PR uses `RESTRICT_ON_SEND` to restrict callbacks `on_send` to specific method names only.
https://docs.rubocop.org/rubocop/1.46/development.html#implementation

Avoid `3.0` parsing as ruby 3 and installing 3.x, instead use `'3.0'` to fix the minor

# NEW
* added support for ruby 3.3

# CHANGED
* increased the minimum rubocop version to ~> 1.61 (from ~> 1.32.0) -- **potentially breaking**

# BREAKING
* drop support for ruby 2.6

This PR adds support for RuboCop's Plugin feature.

It replaces the ad-hoc `Inject` hack with the RuboCop plugin system introduced in RuboCop 1.72.

- rubocop/rubocop#13792
- https://docs.rubocop.org/rubocop/plugin_migration_guide.html

Accordingly, rubocop-airbnb has been updated to require specific versions of the following
RuboCop extension plugins it depends on

- rubocop-performance (`~> 1.24`)
- rubocop-rails (`~> 2.30`)
- rubocop-rspec (`~> 3.5`)

The most significant change is that rubocop-rspec has been updated from version 2 to version 3.
As a result, `RSpec/Capybara` and `RSpec/FactoryBot` have been extracted into the following extension gems:

- rubocop-capybara
- rubocop-factory_bot

This PR adds dependencies on both rubocop-capybara and rubocop-rspec extensions to maintain
the previous rubocop-rspec configuration.

`RSpec/FilePath` has been split into `RSpec/SpecFilePathFormat` and `RSpec/SpecFilePathSuffix`,
so the original disabling has been retained in the configuration.
Similarly, `RSpec/Capybara/FeatureMethods` remains disabled as `RSpec/Dialect`.
https://github.com/rubocop/rubocop-rspec/blob/v3.5.0/config/obsoletion.yml

Resolves rubocop/rubocop-factory_bot#147.

…icatePrefix` (airbnb#216)

* chore: fix warnings about using deprecated `Naming/PredicateName` cop

The cop was renamed to `Naming/PredicatePrefix` in `rubocop` `v1.76.0`,
so we should use that one instead.

Fixes airbnb#215.

* build(deps): bump minimum required `rubocop` version to `~> 1.76`

* docs: update `CHANGELOG.md` changes to be released