fixed registryEndpoint string

pkg/minikube/extract/testdata/test.json

 {
+	"Hint: This is not a URL, come on.": "",
 	"Holy cow I'm in a loop!": "Something else",
-	"This was a choice: %s": "Something"
+	"This is a variable with a string assigned": "",
+	"This was a choice: %s": "Something",
+	"Wow another string: %s": ""
 }
\ No newline at end of file

test/integration/addons_test.go

@@ -211,7 +211,7 @@ func testRegistry(t *testing.T) {
 			t.Fatalf("failed to read minikubeIP: %v", err)
 		}
 
-		registryEndpoint := "http://" + strings.TrimSpace(s) + "5000"
+		registryEndpoint := "http://" + strings.TrimSpace(s) + ":5000"
 		u, err := url.Parse(registryEndpoint)
 
 		if err != nil {