Update pipeline to write creds file

Author: Jonathan Wenger

.github/workflows/gem-push.yml

@@ -21,6 +21,14 @@ jobs:
  ruby-version: "2.6"
  bundler-cache: true # Caches gems between runs
 
+ - name: Write AvaTax credentials to credentials.yaml
+ run: |
+ cat <<EOF > spec/credentials.yaml
+ endpoint: https://sandbox-rest.avatax.com
+ username: "${{ secrets.SANDBOX_USERNAME }}"
+ password: "${{ secrets.SANDBOX_PASSWORD }}"
+ EOF
+
  - name: Install dependencies
  run: bundle install