Adds walkthrough video for credentials setup

module3/lessons/testing_tools_for_api_consumption.md

@@ -25,6 +25,8 @@ Slides are available [here](https://github.com/turingschool/backend-curriculum-s
 
 ## Required Setup
 
+[📺 Here is a walkthrough video to help you set up your Rails Application Credentials.](https://drive.google.com/file/d/1Cy598b1W1d7nZ-gv6ur_gPmAGOmaD3Gi/view?usp=sharing)
+
 - [Request a Propublica API Key](https://www.propublica.org/datastore/api/propublica-congress-api)
 - Clone [the House Salad 7](https://github.com/turingschool-examples/house-salad-7/tree/testing-setup) 
   - (forking is optional since we won't ask you to push up any changes)
@@ -129,6 +131,8 @@ RSpec.describe 'Senator Search' do
 end
 ```
 
+---
+
 ## Mocking Network Requests
 
 The [setup branch](https://github.com/turingschool-examples/house-salad-7/tree/testing-setup) for this class has implemented a test to ensure that we are able to hit our API and display some data from the response. However, our test is actually hitting the Propublica API every time it runs. There are many reasons we wouldn't want to do this: