feat: replace kernel with URI for Ruby 3 compatibility

In Ruby 2, Kernel.open worked for both local and remote files.
In Ruby 3, this was changed such that Kernel.open would only open local files.
URI.open became the prefered syntax for opening remote files.
ruby/open-uri@53862fa

Co-authored-by: Nate Perry <[email protected]>

lib/qualtrics_api/response_export.rb

@@ -34,7 +34,7 @@ def file_url
     def open(&block)
       raise QualtricsAPI::FileNotReadyError, "Cannot open exported file because the file url is missing." if file_url.nil?
 
-      Kernel.open(file_url, **QualtricsAPI.connection(self).headers, &block)
+      URI.open(file_url, **QualtricsAPI.connection(self).headers, &block)
     end
   end
 end

spec/lib/response_export_spec.rb

@@ -109,7 +109,7 @@
 
     it "conforms to ruby 3 keyword-argument format" do
       subject.instance_variable_set(:@file_url, "some_url")
-      expect(Kernel).to receive(:open) do |*args, **kwargs|
+      expect(URI).to receive(:open) do |*args, **kwargs|
         expect(args).to eq ["some_url"]
         expect(kwargs.class).to eq Faraday::Utils::Headers
       end
@@ -128,7 +128,7 @@
       end
 
       it "opens the linked file with the file_url and qualtrics connection" do
-        expect(Kernel).to receive(:open).with("some_url", connection_headers)
+        expect(URI).to receive(:open).with("some_url", connection_headers)
         subject.open
       end
     end