Add external links to the 'docs' directory

[github-learning-lab]

With the addition of links to our code base, we should add a unit test as one of our CircleCI jobs that run whenever it builds.

Let's add a test using HTMLProofer to test for any broken links, images, or HTML. By adding this to our testlinks unit test, HTMLProofer will test our code before it gets merged.

CircleCI allows us to configure multiple jobs using a feature called Workflows. Since we're interested in performing two jobs (a build, and a test for links), we'll use Workflows.

I've already added some things necessary for HTMLProofer test to run, and implemented the use of the Workflows feature. Next, replace the placeholder text with the following:

bundle exec htmlproofer ./_site --check-html

Step 9: Add an HTMLProofer unit test

Let's make sure all links are valid by adding a link checker unit test.

⌨️ Activity: Check for broken links using CircleCI

1. In this pull request, replace the REPLACE-ME-WITH-SCRIPT placeholder text with bundle exec htmlproofer ./_site --check-html. You can do this by editing the file from the Files changed tab, or by scrolling down and accepting the suggested change.

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I'll respond below with your next step.

[github-learning-lab]

Suggested change

	command: REPLACE-ME-WITH-SCRIPT
	command: bundle exec htmlproofer ./_site --check-html