fix: use ',' as delimiter for key-value pairs in labelSelector

Signed-off-by: cmaune <[email protected]>

Author: cmaune

spring-cloud-kubernetes-client-discovery/src/main/java/org/springframework/cloud/kubernetes/client/discovery/catalog/KubernetesCatalogWatchContext.java

@@ -48,7 +48,7 @@ static List<EndpointNameAndNamespace> state(Stream<V1ObjectReference> references
 	}
 
 	static String labelSelector(Map<String, String> labels) {
-		return labels.entrySet().stream().map(en -> en.getKey() + "=" + en.getValue()).collect(Collectors.joining("&"));
+		return labels.entrySet().stream().map(en -> en.getKey() + "=" + en.getValue()).collect(Collectors.joining(","));
 	}
 
 }