StandardRb: update load_tests for UselessAssignment

Change the `cache_file` as the 2nd value were never used.

Author: D-system

.standard_todo.yml

@@ -5,7 +5,6 @@ ignore:
 - features/support/load_tests.rb:
   - Style/For
   - Security/Open
-  - Lint/UselessAssignment
 - lib/csvlint/cli.rb:
   - Style/NonNilCheck
 - lib/csvlint/csvw/column.rb:

features/support/load_tests.rb

@@ -26,7 +26,7 @@ def cache_file(filename)
       f.puts URI.open(uri, "rb").read
     end
   end
-  [uri, file]
+  uri
 end
 
 unless File.exist? SCRIPT_FILE_PATH
@@ -66,7 +66,7 @@ def cache_file(filename)
     file.puts ""
 
     manifest["entries"].each do |entry|
-      action_uri, action_file = cache_file(entry["action"])
+      action_uri = cache_file(entry["action"])
       metadata = nil
       provided_files = []
       missing_files = []
@@ -98,7 +98,7 @@ def cache_file(filename)
         missing_files << URI.join(action_uri, "csv-metadata.json").to_s
       end
       entry["implicit"]&.each do |implicit|
-        implicit_uri, implicit_file = cache_file(implicit)
+        implicit_uri = cache_file(implicit)
         provided_files << implicit_uri.to_s
         unless implicit_uri == metadata
           file.puts "\t\tAnd I have a file called \"csvw/#{implicit}\" at the url \"#{implicit_uri}\""