docs(readme): add quickstart clarity on GIT_EMAIL

Author: bcanseco

README.md

@@ -38,7 +38,7 @@
    ![](./.github/images/create-new-file.png)
 1. In the **Name your file...** field, type in `.github/workflows/main.yml`
    ![](./.github/images/name-new-file.png)
-1. Paste in one of the YAML file contents below, depending on what you want to do.
+1. Paste in one of the YAML file contents below, depending on what you want to do. Be sure to update `GIT_EMAIL`.
 1. Click the **Commit new file** button at the bottom of the page. You're all set!
 
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