Simplify Rakefile - remove unnecessary build task

The build task was not needed:
- gem release command handles building the gem
- We don't need a separate build step
- The default task can just run specs

This makes the Rakefile cleaner and simpler.

Author: justin808

Rakefile

@@ -3,14 +3,4 @@ RSpec::Core::RakeTask.new(:spec) do |t|
   t.pattern = 'spec/cypress_on_rails/*_spec.rb'
 end
 
-# Manually define build task (normally provided by bundler/gem_tasks)
-# We don't use bundler/gem_tasks because it conflicts with our custom release task
-desc "Build gem into pkg directory"
-task :build do
-  require_relative 'lib/cypress_on_rails/version'
-  sh "gem build cypress-on-rails.gemspec"
-  sh "mkdir -p pkg"
-  sh "mv cypress-on-rails-#{CypressOnRails::VERSION}.gem pkg/"
-end
-
-task default: %w[spec build]
+task default: :spec