`loadFromDefault` fails if the KUBECONFIG env variable ends with path delimiter.

[sweko]

Describe the bug
calling loadFromDefault fails if the KUBECONFIG env variable ends with path delimiter.

** Client Version **
0.14.1

** Server Version **
N/A

To Reproduce
Set the KUBECONFIG env variable so that the last character is the path delimiter ; on Windows, : on Linux
export KUBECONFIG=$KUBECONFIG:
Run the examples

Expected behavior
loadFromDefault should load the configuration from the files, ignoring empty entries in KUBECONFIG .

** Example Code**
In console:

export KUBECONFIG=$KUBECONFIG:

In code:

const kc = new k8s.KubeConfig();
kc.loadFromDefault()

Environment (please complete the following information):

• OS: Windows and Linux (WSL Ubuntu)
• NodeJS Version N/A
• Cloud runtime N/A

[sweko]

Closed by #628