Bump rack from 2.0.5 to 2.1.4.3

run tests - RUBY_VERSION=2.6.10

run tests - RUBY_VERSION=2.7.7

run tests - RUBY_VERSION=3.0.5

run tests - RUBY_VERSION=3.1.3

run tests - RUBY_VERSION=3.2.0

run tests - RUBY_VERSION=jruby-9.3.9.0

run tests - RUBY_VERSION=jruby-9.4.0.0

run tests - RUBY_VERSION=truffleruby-22.3.0