Switch chainguard images to alternative Alpine-based images

On July 15, 2024, Chainguard will be changing their base images to be
based on their own custom Wolfi base. This means they will be dropping
support for a number of platforms, keeping only linux/arm64 and linux/amd64.

Switch to their alternative Alpine-based images to maintain support for
other platforms such as linux/s390x and linux/ppc64le.

See https://www.chainguard.dev/unchained/changes-to-static-git-and-busybox-developer-images-2
for more details.

.ko.yaml

@@ -1 +1 @@
-defaultBaseImage: cgr.dev/chainguard/static@sha256:67a1b00e0134e2b3a614c7198a26f7deed9d11b7acad4d52c79c0cfd47a2eae7
+defaultBaseImage: ghcr.io/wolfi-dev/static:alpine@sha256:2a0e1651c779fd24cea09a5ec6a0437117ff5d1fbe5fafe78020dfb8cc757018

src/api/resources/import-resources-pipelinerun.yaml

@@ -57,7 +57,7 @@ spec:
             - name: repo
           steps:
             - name: clone
-              image: cgr.dev/chainguard/git:latest@sha256:2c70afb3b34ca5feab37c5826c32dae6e0c48549486fdf6be93faf928b658efe  # 2.41
+              image: ghcr.io/wolfi-dev/git:alpine@sha256:3a118879b998f146812c11630805863f8a769587460938cbcc1daca874d9b57c  # 2.45
               env:
                 - name: PARAM_URL
                   value: $(params.repositoryURL)