Revert "Make word "path" plural"

This reverts commit 1dbc4c3fee.

spec/spec_helper/load_path_spec.rb

@@ -31,7 +31,7 @@ RSpec.describe $LOAD_PATH do
     expect($LOAD_PATH).to include(THIRD_PARTY_DIR)
   end
 
-  it('should already have unique paths') do
+  it('should already have unique path') do
     expect($LOAD_PATH).to match_array($LOAD_PATH.uniq!)
   end
 end