[BUG] Add tracks attr_reader to Configuration

[alexsmartens]

Description:
This pull request adds the missing tracks attribute reader to the Rack::Attack::Configuration class. This change ensures that the tracks attribute is accessible, consistent with other attributes such as safelists, blocklists, and throttles.

How this was discovered?

> Rack::Attack.tracks.clear
=> warning: #<Class:Rack::Attack>#tracks at /.rbenv/versions/3.1.3/lib/ruby/3.1.0/forwardable.rb:157 forwarding to private method Rack::Attack::Configuration#tracks
/.rbenv/versions/3.1.3/lib/ruby/3.1.0/forwardable.rb:236:in `tracks': undefined method `tracks' for #<Rack::Attack::Configuration:0x000000010c09e978...

Changes:

• Added :tracks to the attr_reader in lib/rack/attack/configuration.rb.
• Updated spec/configuration_spec.rb to include tests for the tracks attribute alongside safelists, blocklists, and throttles.

Testing:

• Verified that all existing tests pass.
• Added new tests to check the accessibility of the tracks attribute.

This update enhances the completeness and consistency of the Rack::Attack::Configuration class, ensuring that all attributes are properly exposed and tested.

[alexsmartens]

@santib can you please re-trigger the workflows, they were failing because how I required spec_helper. I've updated that so we should be good

[alexsmartens]

@santib revised

[alexsmartens]

@santib the workflows failed because I used RSpec matchers. I revised the spec to use minitest

[santib]

Thanks!