allow caching and overriding single_snapshot for kaniko

[omrishiv]

What this PR does / why we need it: In our environment, image builds take a long time because the base layer is large and our updates are small. We have to use the in-cluster builder and this allows us to snapshot and cache the intermediate layers so subsequent builds become faster.

Which issue(s) this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close the issue(s) when PR gets merged): Fixes #

Special notes for your reviewer:

1. Please confirm that if this PR changes any image versions, then that's the sole change this PR makes.

This PR should be backwards compatible with older versions.

Release note:

Enables creation of a cluster builder with the ability to cache and not use single_snapshots to enable faster incremental builds in certain situations:

        cluster_builder = ClusterBuilder(registry=constants.DEFAULT_DOCKER_REGISTRY,
                                         base_image=self._base_image_name,
                                         preprocessor=preprocessor,
                                         image_name=image_name,
                                         dockerfile_path='Dockerfile',
                                         context_source=create_minio_context_source(),
                                         cache=True,
                                         single_snapshot=False)

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[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by: OmriShiv To complete the pull request process, please assign jinchihe after the PR has been reviewed. You can assign the PR to them by writing /assign @jinchihe in a comment when ready.

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[xauthulei]

@OmriShiv , please accept the CLA for the contribution firstly, Thanks

[omrishiv]

@xauthulei Thank you, working on it with the org