Provide a Config.fromKubeconfig(Path|File) method and deprecate the current ones

[manusa]

Description

Part of #6516

Config offers several static helper methods to instantiate it using different procedures.

At the moment, the fromKubeconfig methods are intricate and confusing, especially the one that accepts a path String parameter:

kubernetes-client/kubernetes-client-api/src/main/java/io/fabric8/kubernetes/client/Config.java

Line 809 in 150c111

public static Config fromKubeconfig(String kubeconfigContents) {

kubernetes-client/kubernetes-client-api/src/main/java/io/fabric8/kubernetes/client/Config.java

Line 814 in 150c111

public static Config fromKubeconfig(String context, String kubeconfigContents, String kubeconfigPath) {

We should deprecate the one with the kubeconfigPath parameter and provide a convenient fromKubeconfig(Path|File) method.

In the future, this method can be improved to support #6240 by making it variadic.