Updates rubocop dep

spec/app/controllers/vuln_api_spec.rb

@@ -7,7 +7,7 @@ describe WPScan::Controller::VulnApi do
 
   before do
     WPScan::ParsedCli.options = rspec_parsed_options(cli_args)
-    WPScan::DB::VulnApi.instance_variable_set(:'@default_request_params', nil)
+    WPScan::DB::VulnApi.instance_variable_set(:@default_request_params, nil)
   end
 
   describe '#cli_options' do

spec/app/models/plugin_spec.rb

@@ -172,7 +172,7 @@ describe WPScan::Model::Plugin do
 
     after do
       expect(plugin.vulnerabilities).to eq @expected
-      expect(plugin.vulnerable?).to eql @expected.empty? ? false : true
+      expect(plugin.vulnerable?).to eql !@expected.empty?
     end
 
     context 'when plugin not in the DB' do

spec/app/models/theme_spec.rb

@@ -200,7 +200,7 @@ describe WPScan::Model::Theme do
 
     after do
       expect(theme.vulnerabilities).to eq @expected
-      expect(theme.vulnerable?).to eql @expected.empty? ? false : true
+      expect(theme.vulnerable?).to eql !@expected.empty?
     end
 
     context 'when theme not in the DB' do