Update for lint errors

Author: rstacruz

test/fixture/markdown_plugin_invalid_test.js

@@ -18,6 +18,6 @@ describe('fixture/markdown plugin invalid:', function () {
 
   it('fails', function () {
     expect(this.err).toExist()
-    expect(this.err.message).toEqual(`Can't find module 'markdown-it-lalalala'`)
+    expect(this.err.message).toEqual("Can't find module 'markdown-it-lalalala'")
   })
 })

test/index/missing_pages_test.js

@@ -28,6 +28,6 @@ describe('index/missing pages:', function () {
 
   it('works', function () {
     expect(this.err).toExist()
-    expect(this.err.message).toEqual(`Invalid reference 'docs/getting-started.md'`)
+    expect(this.err.message).toEqual("Invalid reference 'docs/getting-started.md'")
   })
 })