Update dependency gcr.io/kaniko-project/executor to v1.8.0

.gitlab-ci.yml

@@ -3,7 +3,7 @@ build:
   image:
     # We need a shell to provide the registry credentials, so we need to use the
     # kaniko debug image (https://github.com/GoogleContainerTools/kaniko#debug-image)
-    name: gcr.io/kaniko-project/executor:v1.7.0-debug
+    name: gcr.io/kaniko-project/executor:v1.8.0-debug
     entrypoint: [""]
   script:
     - mkdir -p /kaniko/.docker/