Update running-code-scanning-in-your-ci-system.md

[casals]

Why:

Fixes #167 .

What's being changed:

Rewrote the first paragraph of Adding the CodeQL runner to your CI system and added the script snippet contained in the issue. Broke the snippet in two lines (rather than using a && concatenation) for better readability.

Check off the following:

• All of the tests are passing.
• I have reviewed my changes in staging.
• For content changes, I have reviewed the localization checklist
• For content changes, I have reviewed the Content style guide for GitHub Docs.

[hubwriter]

@casals - thanks for making this update to the docs.
Your change LGTM 👍

[hubwriter]

We'll merge this shortly. Thanks again