feat(actions): enable github code scanning
feat(actions): enable github code scanning

https://github.blog/2020-09-30-code-scanning-is-now-available/

OurWorldInData/owid-grapher,OurWorldInData/owid-grapher,OurWorldInData/owid-grapher,owid/owid-grapher,OurWorldInData/owid-grapher,owid/owid-grapher,owid/owid-grapher,owid/owid-grapher,owid/owid-grapher,OurWorldInData/owid-grapher