Make plugin show erb spec more realistic

Change-Id: I19848500c86f52988f3b04d80f9277cd54cfeecd
Reviewed-on: https://gerrit.instructure.com/c/canvas-lms/+/258953
Tested-by: Service Cloud Jenkins <svc.cloudjenkins@instructure.com>
Reviewed-by: Cody Cutrer <cody@instructure.com>
QA-Review: Cody Cutrer <cody@instructure.com>
Product-Review: Cody Cutrer <cody@instructure.com>

spec/views/plugins/show.html.erb_spec.rb

@@ -25,14 +25,15 @@ describe "plugins/show" do
     plugin = double(
       id: 'some_plugin',
       name: "Some Plugin",
-      settings_partial: "settings_header"
+      settings_partial: "settings_header",
+      test_cluster_inherit?: false
     )
     plugin_setting = PluginSetting.new()
 
     assign(:plugin, plugin)
     assign(:plugin_setting, plugin_setting)
     allow(view).to receive(:plugin_path).and_return("/some/path")
-    allow(view).to receive(:params).and_return({id: 'some_plugin'})
+    allow(view).to receive(:params).and_return(ActionController::Parameters.new({id: 'some_plugin'}))
     render 'plugins/show'
     expect(response.body).to match("Return to plugins list")
   end