RawCustomResourceOperationsImpl#delete should return a boolean value indicating deletion status

[rohanKanojia]

Right now we have these delete methods in API which seems to work okay but they fail with 404 in case resource is not present in the cluster:

kubernetes-client/kubernetes-client/src/main/java/io/fabric8/kubernetes/client/dsl/internal/RawCustomResourceOperationsImpl.java

Lines 427 to 459 in 3e5cb2f

	public Map<String, Object> delete(String namespace) {
	return makeCall(fetchUrl(namespace, null, null), null, HttpCallMethod.DELETE);
	}
	/**
	* Delete all custom resources in a specific namespace
	*
	* @param namespace desired namespace
	* @param cascading whether dependent object need to be orphaned or not. If true/false, the "orphan"
	* finalizer will be added to/removed from the object's finalizers list.
	* @return deleted objects as HashMap
	* @throws IOException in case of any network/parsing exception
	*/
	public Map<String, Object> delete(String namespace, boolean cascading) throws IOException {
	return makeCall(fetchUrl(namespace, null, null), objectMapper.writeValueAsString(fetchDeleteOptions(cascading, null)), HttpCallMethod.DELETE);
	}
	/**
	* Delete all custom resources in a specific namespace
	*
	* @param namespace desired namespace
	* @param deleteOptions object provided by Kubernetes API for more fine grained control over deletion.
	* For more information please see https://kubernetes.io/docs/reference/generated/kubernetes-api/v1.16/#deleteoptions-v1-meta
	* @return deleted object as HashMap
	* @throws IOException in case of any network/object parse problems
	*/
	public Map<String, Object> delete(String namespace, DeleteOptions deleteOptions) throws IOException {
	return makeCall(fetchUrl(namespace, null, null), objectMapper.writeValueAsString(deleteOptions), HttpCallMethod.DELETE);
	}
	/**
	* Delete a custom resource in a specific namespace
	*

We discovered this behavior in one of the issues[0] on Eclipse JKube. I think we should align this behavior with standard deletion API's to return false if resource requested for deletion doesn't exist in server:

kubernetes-client/kubernetes-client/src/main/java/io/fabric8/kubernetes/client/dsl/base/BaseOperation.java

Lines 699 to 703 in 3e5cb2f

	} catch (KubernetesClientException e) {
	if (e.getCode() != HttpURLConnection.HTTP_NOT_FOUND) {
	throw e;
	}
	return false;

[0] eclipse-jkube/jkube#534