Remove $LOAD_PATH.uniq! because $LOAD_PATH does not contain any duplicate path

spec/spec_helper/load_path_spec.rb

@@ -27,4 +27,7 @@ RSpec.describe $LOAD_PATH do
   it('should contain THIRD_PARTY_DIR') do
     expect($LOAD_PATH).to include(THIRD_PARTY_DIR)
   end
+  it('should already have unique path') do
+    expect($LOAD_PATH).to match_array($LOAD_PATH.uniq!)
+  end
 end