Allow running specs against Pageflow edge

The reusable workflow now runs specs against experimental Rails
versions which require Pageflow to be installed from a git source.

REDMINE-19438

Gemfile

@@ -3,7 +3,14 @@ source 'https://rubygems.org'
 # Specify your gem's dependencies in pageflow-vr.gemspec
 gemspec
 
-group :development, :test do
-  # Help Bundler resolve dependencies
-  gem 'rails', '~> 5.2.0'
+if ENV['PAGEFLOW_DEPENDENCIES'] == 'experimental'
+  git 'https://github.com/codevise/pageflow', branch: 'edge', glob: '**/*.gemspec' do
+    gem 'pageflow'
+    gem 'pageflow-support'
+  end
+else
+  group :development, :test do
+    # Help Bundler resolve dependencies
+    gem 'rails', '~> 5.2.0'
+  end
 end

pageflow-vr.gemspec

@@ -23,6 +23,12 @@ Gem::Specification.new do |spec|
   spec.add_development_dependency 'bundler', ['>= 1.12', '< 3']
   spec.add_development_dependency 'pageflow-support', ['>= 14', '< 17']
   spec.add_development_dependency 'rake', '~> 12.0'
-  spec.add_development_dependency 'rspec-rails', '~> 3.0'
+
+  if ENV['PAGEFLOW_DEPENDENCIES'] == 'experimental'
+    spec.add_development_dependency 'rspec-rails', '~> 6.0'
+  else
+    spec.add_development_dependency 'rspec-rails', '~> 3.0'
+  end
+
   spec.add_development_dependency 'semmy', '~> 1.0'
 end