feat: add --destination flag for kaniko build

[hedinasr]

Description
We are using Skaffold to build images in our CI. We wanted to push multiple tags for one image so we implemented the use of the --destination kaniko's flag.

It would be used like this:

apiVersion: skaffold/v4beta11
kind: Config
metadata:
  name: base-image
build:
  artifacts:
    - image: base
      kaniko:
        destination:
          - base:test-1
          - base:test-2