Rack 3 update: Patch RspecApiDocumentation module

* and add unit test to check rspec_api_documentation Gem version (will fail when Gem is updated)

Author: jochenehret

spec/support/rspec_api_documentation_patch.rb

@@ -0,0 +1,14 @@
+# Monkey patch to provide a robust read_request_body helper compatible with Rack 3
+# See:
+# https://github.com/zipmark/rspec_api_documentation/pull/550
+# https://github.com/zipmark/rspec_api_documentation/issues/548
+
+module RspecApiDocumentation
+  class ClientBase
+    def read_request_body
+      input = last_request.env['rack.input'] || StringIO.new
+      input.rewind
+      input.read
+    end
+  end
+end

spec/unit/support/rspec_api_documentation_version_spec.rb

@@ -0,0 +1,10 @@
+require 'spec_helper'
+
+RSpec.describe 'rspec_api_documentation gem version' do
+  it 'is pinned to 6.1.0 for the monkey patch compatibility' do
+    spec = Gem.loaded_specs['rspec_api_documentation']
+    # Ensure the gem is loaded; spec_helper requires it in init block.
+    expect(spec).not_to be_nil
+    expect(spec.version.to_s).to eq('6.1.0')
+  end
+end