Add Actions to CodeQL workflow

[martincostello]

The repository has CodeQL setup, but it doesn't run CodeQL analysis for GitHub Actions workflows.

We should add it to the matrix for defence-in-depth given that Actions is a core function of the code in this repository:

shared-workflows/.github/workflows/codeql.yml

Lines 39 to 46 in 4393180

	matrix:
	include:
	- language: go
	build-mode: autobuild
	- language: javascript-typescript
	build-mode: none
	paths-ignore:
	- "**/dist/**"