Fix OpenConfigurator to handle blank yaml files

lib/kangaru/configurators/open_configurator.rb

@@ -16,7 +16,7 @@ def initialize(**)
       def self.from_yaml_file(path)
         raise "path does not exist" unless File.exist?(path)
 
-        attributes = YAML.load_file(path).symbolise
+        attributes = YAML.load_file(path)&.symbolise || {}
 
         new(**attributes)
       end

spec/features/external_config_spec.rb

@@ -68,7 +68,7 @@ module SomeGem
     context "and config exists at the specified path" do
       before { config_path.write(config_file) }
 
-      context "and config file is empty", skip: :bug_fix do
+      context "and config file is empty" do
         let(:config_file) { "" }
 
         include_examples :does_not_set_external_config

spec/kangaru/configurators/open_configurator_spec.rb

@@ -35,7 +35,7 @@
     context "when specified file exists" do
       let(:exists?) { true }
 
-      context "and file is empty", skip: :bug_fix do
+      context "and file is empty" do
         let(:string_hash) { nil }
 
         it "does not raise any errors" do