Use ghcr.io/distroless/static as base image

This also updates the Windows nanoserver base image used by the
entrypoint image, and updates the Go version used to build the combine
command to the latest Go release 1.18.3.

.ko.yaml

@@ -1,4 +1,4 @@
-defaultBaseImage: gcr.io/distroless/static:nonroot
+defaultBaseImage: ghcr.io/distroless/static
 baseImageOverrides:
   # git-init uses a base image that includes Git, and supports running either
   # as root or as user nonroot with UID 65532.

tekton/publish.yaml

@@ -80,7 +80,7 @@ spec:
       cp ${DOCKER_CONFIG} /workspace/docker-config.json
 
   - name: create-ko-yaml
-    image: golang:1.17.8
+    image: golang:1.18.3
     script: |
       #!/bin/sh
       set -ex
@@ -95,13 +95,13 @@ spec:
 
       # Combine Distroless with a Windows base image, used for the entrypoint image.
       COMBINED_BASE_IMAGE=$(go run ./vendor/github.com/tektoncd/plumbing/cmd/combine/main.go \
-        gcr.io/distroless/static:nonroot \
-        mcr.microsoft.com/windows/nanoserver:1809 \
+        ghcr.io/distroless/static \
+        mcr.microsoft.com/windows/nanoserver:ltsc2022 \
         ${CONTAINER_REGISTRY}/$(params.package)/combined-base-image:latest)
 
       cat <<EOF > ${PROJECT_ROOT}/.ko.yaml
       # This matches the value configured in .ko.yaml
-      defaultBaseImage: gcr.io/distroless/static:nonroot
+      defaultBaseImage: ghcr.io/distroless/static
       baseImageOverrides:
         # Use the combined base image for images that should include Windows support.
         $(params.package)/cmd/entrypoint: ${COMBINED_BASE_IMAGE}