Update github/codeql-action action to v2

Editor assessment

Update github/codeql-action action to v2 is a complete dependency statement: the action and the new major version are explicit, and a major security-scanner bump is exactly what readers want flagged. The build type is accurate, the missing scope is tolerable for repo-level tooling, and no body is required for a mechanical upgrade. No footer beyond the project reference applies. Clean and publishable. The major-version flag is the salient fact for a scanner upgrade, and it is stated with the exact action name.