SPIKE: fix pullImage for when source already contains digest

This fixes the current implementation to correctly pullImage when the source image from annotations already contains the image digest.

```
apiVersion: v0
kind: ImagesLock
metadata:
  generatedAt: "2024-09-24T07:19:33.65058Z"
  generatedBy: Distribution Tooling for Helm
chart:
  name: test-chart1
  version: 0.1.0
  appVersion: 1.16.0
images:
  - name: service-a
    image: example.com/deploy/aaaaaa/service-a:0.3.0@sha256:f43290f7f2e3c3c8281bee512d216b7c604fd92501b3b4522df9333b1921f867
    chart: test-chart1
    digests:
      - digest: sha256:f43290f7f2e3c3c8281bee512d216b7c604fd92501b3b4522df9333b1921f867
        arch: linux/amd64
```

Failure
```
    ✘  failed to pull images: failed to pull image "service-a": parsing reference " example.com/deploy/aaaaaa/service-a:0.3.0@sha256:f43290f7f2e3c3c8281bee512d216b7c604fd92501b3b4522df9333b1921f867@sha256:f43290f7f2e3c3c8281bee512d216b7c604fd92501b3b4522df9333b1921f867": could not parse reference:  example.com/deploy/aaaaaa/service-a:0.3.0@sha256:f43290f7f2e3c3c8281bee512d216b7c604fd92501b3b4522df9333b1921f867@sha256:f43290f7f2e3c3c8281bee512d216b7c604fd92501b3b4522df9333b1921f867
```

pkg/chartutils/images.go

@@ -288,8 +288,11 @@ func getImageLayoutDir(imagesDir string, dgst imagelock.DigestInfo) string {
 
 func pullImage(image string, digest imagelock.DigestInfo, imagesDir string, o crane.Options) (string, error) {
 	imgDir := getImageLayoutDir(imagesDir, digest)
-
-	src := fmt.Sprintf("%s@%s", image, digest.Digest)
+
+	var src = fmt.Sprintf("%s@%s", image, digest.Digest)
+	if strings.Contains(image, string(digest.Digest)) {
+		src = image
+	}
 	ref, err := name.ParseReference(src, o.Name...)
 	if err != nil {
 		return "", fmt.Errorf("parsing reference %q: %w", src, err)