feat: add support of local '.tar.gz' file inside the kaniko container

[JordanGoasdoue]

Fixes #567

Description

feat: add support of local build context format file : '.tar.gz' inside the kaniko container

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• Includes unit tests
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Reviewer Notes

• The code flow looks good.
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Release Notes

Describe any changes here so maintainer can include it in the release notes, or delete this block.

• kaniko allow a new build context tar://path/to/.tar.gz to use in kaniko container

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[JordanGoasdoue]

@googlebot I signed it!

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[tejal29]

Thank you for this feature!! this is looking great. just few comments,.

[JordanGoasdoue]

Thank you very much for your comments and review @tejal29 . It's a pleasure for me to finally contribute here.

It's working now with the unit tests, you can review again 👌

Cheers

[tejal29]

Verified this manually by creating context.tar.
Thank you for your contribution.