Fix name of ko in cloudbuild

Signed-off-by: Jeff Mendoza <jlm@jlm.name>

cloudbuild.yaml

@@ -1,7 +1,7 @@
 steps:
 - name: golang:1.21
   entrypoint: go
-  args: ['install', 'github.com/ko-build/ko@v0.15.2']
+  args: ['install', 'github.com/google/ko@v0.15.2']
 - name: golang:1.21
   entrypoint: bash
   args: ['-c', 'KO_DOCKER_REPO="gcr.io/allstar-ossf" /go/bin/ko publish ./cmd/allstar > container']