Update README.md

Author: SiaraMist

README.md

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-# codeql-codespaces-template
+Welcome to your shiny new Codespace running CodeQL! We've got everything fired up and running for you to explore CodeQL.
+
+You've got a blank canvas to work on from a git perspective as well. There's a single initial commit with the what you're seeing right now - where you go from here is up to you!
+
+Everything you do here is contained within this one codespace. There is no repository on GitHub yet. If and when you’re ready you can click "Publish Branch" and we’ll create your repository and push up your project. If you were just exploring then and have no further need for this code then you can simply delete your codespace and it's gone forever.
+
+## Running the code tour
+
+We've set up a code tour to help you get familiar with a CodeQL project and how to run queries. To run the code tour:
+
+1. In your codespace, at the bottom of the File Explorer, expand **Code Tour**.
+1. Expand the **CodeQL tutorial**, then click **#1**. 
+1. In the Editor, follow along with the tutorial, and press **Next** when you're ready to move on to the next step.
+
+## Running custom queries
+
+