integration: build using registry-mirror

Signed-off-by: Yoan Blanc <yoan@dosimple.ch>

integration/integration_test.go

@@ -169,6 +169,10 @@ func TestMain(m *testing.M) {
 			name:    "Pushing hardlink base image",
 			command: []string{"docker", "push", config.hardlinkBaseImage},
 		},
+		{
+			name:    "Building kaniko image using registry-mirror",
+			command: []string{"docker", "build", "--registry-mirror", "mirror.gcr.io", "-t", ExecutorImage, "-f", "../deploy/Dockerfile", ".."},
+		},
 	}
 
 	for _, setupCmd := range setupCommands {