Configure Sauce Connect Proxy to work with Github actions

See:
 - https://docs.saucelabs.com/secure-connections/sauce-connect/index.html
 - https://docs.saucelabs.com/dev/cli/saucectl/usage/ci/github-actions/

.github/workflows/ci.yml

@@ -15,6 +15,16 @@ jobs:
       with:
         path: test/node_modules
         key: ${{ runner.os }}-${{ hashFiles('test/yarn.lock') }}
+    - uses: saucelabs/sauce-connect-action@v2
+      with:
+        username: ${{ secrets.SAUCE_USERNAME }}
+        accessKey: ${{ secrets.SAUCE_ACCESS_KEY }}
+        tunnelName: Basecamp-CI_tunnel_name
+        region: us-west
 
     - run: yarn install
     - run: bin/ci
+
+env:
+  SAUCE_USERNAME: ${{ secrets.SAUCE_USERNAME }}
+  SAUCE_ACCESS_KEY: ${{ secrets.SAUCE_ACCESS_KEY }}