Use latest Github checkout action (#3627)
Use latest Github checkout action (#3627)

Signed-off-by: Michael Grosser <05134426bcd175050b08193c02f14ccdafcca088@stp-ip.net>
johnbelamaric/coredns,yongtang/coredns,chrisohaver/coredns,coredns/coredns,miekg/coredns,johnbelamaric/coredns,miekg/coredns